diff --git a/hgext/share.py b/hgext/share.py
--- a/hgext/share.py
+++ b/hgext/share.py
@@ -3,10 +3,42 @@
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
-'''share a common history between several working directories'''
+'''share a common history between several working directories
+
+Automatic Pooled Storage for Clones
+-----------------------------------
+
+When this extension is active, :hg:`clone` can be configured to
+automatically share/pool storage across multiple clones. This
+mode effectively converts :hg:`clone` to :hg:`clone` + :hg:`share`.
+The benefit of using this mode is the automatic management of
+store paths and intelligent pooling of related repositories.
+
+The following ``share.`` config options influence this feature:
+
+``pool``
+    Filesystem path where shared repository data will be stored. When
+    defined, :hg:`clone` will automatically use shared repository
+    storage instead of creating a store inside each clone.
+
+``poolnaming``
+    How directory names in ``share.pool`` are constructed.
+
+    "identity" means the name is derived from the first changeset in the
+    repository. In this mode, different remotes share storage if their
+    root/initial changeset is identical. In this mode, the local shared
+    repository is an aggregate of all encountered remote repositories.
+
+    "remote" means the name is derived from the source repository's
+    path or URL. In this mode, storage is only shared if the path or URL
+    requested in the :hg:`clone` command matches exactly to a repository
+    that was cloned before.
+
+    The default naming mode is "identity."
+'''
 
 from mercurial.i18n import _
-from mercurial import cmdutil, hg, util, extensions, bookmarks
+from mercurial import cmdutil, commands, hg, util, extensions, bookmarks
 from mercurial.hg import repository, parseurl
 import errno
 
@@ -75,10 +107,24 @@ def unshare(ui, repo):
     # update store, spath, svfs and sjoin of repo
     repo.unfiltered().__init__(repo.baseui, repo.root)
 
+# Wrap clone command to pass auto share options.
+def clone(orig, ui, source, *args, **opts):
+    pool = ui.config('share', 'pool', None)
+    if pool:
+        pool = util.expandpath(pool)
+
+    opts['shareopts'] = dict(
+        pool=pool,
+        mode=ui.config('share', 'poolnaming', 'identity'),
+    )
+
+    return orig(ui, source, *args, **opts)
+
 def extsetup(ui):
     extensions.wrapfunction(bookmarks.bmstore, 'getbkfile', getbkfile)
     extensions.wrapfunction(bookmarks.bmstore, 'recordchange', recordchange)
     extensions.wrapfunction(bookmarks.bmstore, 'write', write)
+    extensions.wrapcommand(commands.table, 'clone', clone)
 
 def _hassharedbookmarks(repo):
     """Returns whether this repo has shared bookmarks"""
diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -1421,7 +1421,8 @@ def clone(ui, source, dest=None, **opts)
                  stream=opts.get('uncompressed'),
                  rev=opts.get('rev'),
                  update=opts.get('updaterev') or not opts.get('noupdate'),
-                 branch=opts.get('branch'))
+                 branch=opts.get('branch'),
+                 shareopts=opts.get('shareopts'))
 
     return r is None
 
diff --git a/mercurial/hg.py b/mercurial/hg.py
--- a/mercurial/hg.py
+++ b/mercurial/hg.py
@@ -284,8 +284,50 @@ def copystore(ui, srcrepo, destpath):
         release(destlock)
         raise
 
+def clonewithshare(ui, peeropts, sharepath, source, srcpeer, dest, pull=False,
+                   rev=None, update=True, stream=False):
+    """Perform a clone using a shared repo.
+
+    The store for the repository will be located at <sharepath>/.hg. The
+    specified revisions will be cloned or pulled from "source". A shared repo
+    will be created at "dest" and a working copy will be created if "update" is
+    True.
+    """
+    revs = None
+    if rev:
+        if not srcpeer.capable('lookup'):
+            raise util.Abort(_("src repository does not support "
+                               "revision lookup and so doesn't "
+                               "support clone by revision"))
+        revs = [srcpeer.lookup(r) for r in rev]
+
+    basename = os.path.basename(sharepath)
+
+    if os.path.exists(sharepath):
+        ui.status(_('(sharing from existing pooled repository %s)\n') %
+                  basename)
+    else:
+        ui.status(_('(sharing from new pooled repository %s)\n') % basename)
+        # Always use pull mode because hardlinks in share mode don't work well.
+        # Never update because working copies aren't necessary in share mode.
+        clone(ui, peeropts, source, dest=sharepath, pull=True,
+              rev=rev, update=False, stream=stream)
+
+    sharerepo = repository(ui, path=sharepath)
+    share(ui, sharerepo, dest=dest, update=update, bookmarks=False)
+
+    # We need to perform a pull against the dest repo to fetch bookmarks
+    # and other non-store data that isn't shared by default. In the case of
+    # non-existing shared repo, this means we pull from the remote twice. This
+    # is a bit weird. But at the time it was implemented, there wasn't an easy
+    # way to pull just non-changegroup data.
+    destrepo = repository(ui, path=dest)
+    exchange.pull(destrepo, srcpeer, heads=revs)
+
+    return srcpeer, peer(ui, peeropts, dest)
+
 def clone(ui, peeropts, source, dest=None, pull=False, rev=None,
-          update=True, stream=False, branch=None):
+          update=True, stream=False, branch=None, shareopts=None):
     """Make a copy of an existing repository.
 
     Create a copy of an existing repository in a new directory.  The
@@ -320,6 +362,13 @@ def clone(ui, peeropts, source, dest=Non
     anything else is treated as a revision)
 
     branch: branches to clone
+
+    shareopts: dict of options to control auto sharing behavior. The "pool" key
+    activates auto sharing mode and defines the directory for stores. The
+    "mode" key determines how to construct the directory name of the shared
+    repository. "identity" means the name is derived from the node of the first
+    changeset in the repository. "remote" means the name is derived from the
+    remote's path/URL. Defaults to "identity."
     """
 
     if isinstance(source, str):
@@ -352,6 +401,36 @@ def clone(ui, peeropts, source, dest=Non
         elif destvfs.listdir():
             raise util.Abort(_("destination '%s' is not empty") % dest)
 
+    shareopts = shareopts or {}
+    sharepool = shareopts.get('pool')
+    sharenamemode = shareopts.get('mode')
+    if sharepool:
+        sharepath = None
+        if sharenamemode == 'identity':
+            # Resolve the name from the initial changeset in the remote
+            # repository. This returns nullid when the remote is empty. It
+            # raises RepoLookupError if revision 0 is filtered or otherwise
+            # not available. If we fail to resolve, sharing is not enabled.
+            try:
+                rootnode = srcpeer.lookup('0')
+                if rootnode != node.nullid:
+                    sharepath = os.path.join(sharepool, node.hex(rootnode))
+                else:
+                    ui.status(_('(not using pooled storage: '
+                                'remote appears to be empty)\n'))
+            except error.RepoLookupError:
+                ui.status(_('(not using pooled storage: '
+                            'unable to resolve identity of remote)\n'))
+        elif sharenamemode == 'remote':
+            sharepath = os.path.join(sharepool, util.sha1(source).hexdigest())
+        else:
+            raise util.Abort('unknown share naming mode: %s' % sharenamemode)
+
+        if sharepath:
+            return clonewithshare(ui, peeropts, sharepath, source, srcpeer,
+                                  dest, pull=pull, rev=rev, update=update,
+                                  stream=stream)
+
     srclock = destlock = cleandir = None
     srcrepo = srcpeer.local()
     try:
diff --git a/tests/test-clone.t b/tests/test-clone.t
--- a/tests/test-clone.t
+++ b/tests/test-clone.t
@@ -674,4 +674,342 @@ Test clone from the repository in (emula
   $ hg clone -U -q src dst
   $ hg -R dst log -q
   0:e1bab28bca43
+
+Create repositories to test auto sharing functionality
+
+  $ cat >> $HGRCPATH << EOF
+  > [extensions]
+  > share=
+  > EOF
+
+  $ hg init empty
+  $ hg init source1a
+  $ cd source1a
+  $ echo initial1 > foo
+  $ hg -q commit -A -m initial
+  $ echo second > foo
+  $ hg commit -m second
   $ cd ..
+
+  $ hg init filteredrev0
+  $ cd filteredrev0
+  $ cat >> .hg/hgrc << EOF
+  > [experimental]
+  > evolution=createmarkers
+  > EOF
+  $ echo initial1 > foo
+  $ hg -q commit -A -m initial0
+  $ hg -q up -r null
+  $ echo initial2 > foo
+  $ hg -q commit -A -m initial1
+  $ hg debugobsolete c05d5c47a5cf81401869999f3d05f7d699d2b29a e082c1832e09a7d1e78b7fd49a592d372de854c8
+  $ cd ..
+
+  $ hg -q clone --pull source1a source1b
+  $ cd source1a
+  $ hg bookmark bookA
+  $ echo 1a > foo
+  $ hg commit -m 1a
+  $ cd ../source1b
+  $ hg -q up -r 0
+  $ echo head1 > foo
+  $ hg commit -m head1
+  created new head
+  $ hg bookmark head1
+  $ hg -q up -r 0
+  $ echo head2 > foo
+  $ hg commit -m head2
+  created new head
+  $ hg bookmark head2
+  $ hg -q up -r 0
+  $ hg branch branch1
+  marked working directory as branch branch1
+  (branches are permanent and global, did you want a bookmark?)
+  $ echo branch1 > foo
+  $ hg commit -m branch1
+  $ hg -q up -r 0
+  $ hg branch branch2
+  marked working directory as branch branch2
+  $ echo branch2 > foo
+  $ hg commit -m branch2
+  $ cd ..
+  $ hg init source2
+  $ cd source2
+  $ echo initial2 > foo
+  $ hg -q commit -A -m initial2
+  $ echo second > foo
+  $ hg commit -m second
+  $ cd ..
+
+Clone with auto share from an empty repo should not result in share
+
+  $ mkdir share
+  $ hg --config share.pool=share clone empty share-empty
+  (not using pooled storage: remote appears to be empty)
+  updating to branch default
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  $ ls share
+  $ test -d share-empty/.hg/store
+  $ test -f share-empty/.hg/sharedpath
+  [1]
+
+Clone with auto share from a repo with filtered revision 0 should not result in share
+
+  $ hg --config share.pool=share clone filteredrev0 share-filtered
+  (not using pooled storage: unable to resolve identity of remote)
+  requesting all changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 1 changesets with 1 changes to 1 files
+  updating to branch default
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+
+Clone from repo with content should result in shared store being created
+
+  $ hg --config share.pool=share clone source1a share-dest1a
+  (sharing from new pooled repository b5f04eac9d8f7a6a9fcb070243cccea7dc5ea0c1)
+  requesting all changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 3 changesets with 3 changes to 1 files
+  updating working directory
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  searching for changes
+  no changes found
+  adding remote bookmark bookA
+
+The shared repo should have been created
+
+  $ ls share
+  b5f04eac9d8f7a6a9fcb070243cccea7dc5ea0c1
+
+The destination should point to it
+
+  $ cat share-dest1a/.hg/sharedpath; echo
+  $TESTTMP/share/b5f04eac9d8f7a6a9fcb070243cccea7dc5ea0c1/.hg
+
+The destination should have bookmarks
+
+  $ hg -R share-dest1a bookmarks
+     bookA                     2:e5bfe23c0b47
+
+The default path should be the remote, not the share
+
+  $ hg -R share-dest1a config paths.default
+  $TESTTMP/source1a
+
+Clone with existing share dir should result in pull + share
+
+  $ hg --config share.pool=share clone source1b share-dest1b
+  (sharing from existing pooled repository b5f04eac9d8f7a6a9fcb070243cccea7dc5ea0c1)
+  updating working directory
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  searching for changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 4 changesets with 4 changes to 1 files (+4 heads)
+  adding remote bookmark head1
+  adding remote bookmark head2
+
+  $ ls share
+  b5f04eac9d8f7a6a9fcb070243cccea7dc5ea0c1
+
+  $ cat share-dest1b/.hg/sharedpath; echo
+  $TESTTMP/share/b5f04eac9d8f7a6a9fcb070243cccea7dc5ea0c1/.hg
+
+We only get bookmarks from the remote, not everything in the share
+
+  $ hg -R share-dest1b bookmarks
+     head1                     3:4a8dc1ab4c13
+     head2                     4:99f71071f117
+
+Default path should be source, not share.
+
+  $ hg -R share-dest1b config paths.default
+  $TESTTMP/source1a
+
+Clone from unrelated repo should result in new share
+
+  $ hg --config share.pool=share clone source2 share-dest2
+  (sharing from new pooled repository 22aeff664783fd44c6d9b435618173c118c3448e)
+  requesting all changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 2 changesets with 2 changes to 1 files
+  updating working directory
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  searching for changes
+  no changes found
+
+  $ ls share
+  22aeff664783fd44c6d9b435618173c118c3448e
+  b5f04eac9d8f7a6a9fcb070243cccea7dc5ea0c1
+
+remote naming mode works as advertised
+
+  $ hg --config share.pool=shareremote --config share.poolnaming=remote clone source1a share-remote1a
+  (sharing from new pooled repository 195bb1fcdb595c14a6c13e0269129ed78f6debde)
+  requesting all changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 3 changesets with 3 changes to 1 files
+  updating working directory
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  searching for changes
+  no changes found
+  adding remote bookmark bookA
+
+  $ ls shareremote
+  195bb1fcdb595c14a6c13e0269129ed78f6debde
+
+  $ hg --config share.pool=shareremote --config share.poolnaming=remote clone source1b share-remote1b
+  (sharing from new pooled repository c0d4f83847ca2a873741feb7048a45085fd47c46)
+  requesting all changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 6 changesets with 6 changes to 1 files (+4 heads)
+  updating working directory
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  searching for changes
+  no changes found
+  adding remote bookmark head1
+  adding remote bookmark head2
+
+  $ ls shareremote
+  195bb1fcdb595c14a6c13e0269129ed78f6debde
+  c0d4f83847ca2a873741feb7048a45085fd47c46
+
+request to clone a single revision is respected in sharing mode
+
+  $ hg --config share.pool=sharerevs clone -r 4a8dc1ab4c13 source1b share-1arev
+  (sharing from new pooled repository b5f04eac9d8f7a6a9fcb070243cccea7dc5ea0c1)
+  adding changesets
+  adding manifests
+  adding file changes
+  added 2 changesets with 2 changes to 1 files
+  updating working directory
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  no changes found
+  adding remote bookmark head1
+
+  $ hg -R share-1arev log -G
+  @  changeset:   1:4a8dc1ab4c13
+  |  bookmark:    head1
+  |  tag:         tip
+  |  user:        test
+  |  date:        Thu Jan 01 00:00:00 1970 +0000
+  |  summary:     head1
+  |
+  o  changeset:   0:b5f04eac9d8f
+     user:        test
+     date:        Thu Jan 01 00:00:00 1970 +0000
+     summary:     initial
+  
+
+making another clone should only pull down requested rev
+
+  $ hg --config share.pool=sharerevs clone -r 99f71071f117 source1b share-1brev
+  (sharing from existing pooled repository b5f04eac9d8f7a6a9fcb070243cccea7dc5ea0c1)
+  updating working directory
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  searching for changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 1 changesets with 1 changes to 1 files (+1 heads)
+  adding remote bookmark head1
+  adding remote bookmark head2
+
+  $ hg -R share-1brev log -G
+  o  changeset:   2:99f71071f117
+  |  bookmark:    head2
+  |  tag:         tip
+  |  parent:      0:b5f04eac9d8f
+  |  user:        test
+  |  date:        Thu Jan 01 00:00:00 1970 +0000
+  |  summary:     head2
+  |
+  | @  changeset:   1:4a8dc1ab4c13
+  |/   bookmark:    head1
+  |    user:        test
+  |    date:        Thu Jan 01 00:00:00 1970 +0000
+  |    summary:     head1
+  |
+  o  changeset:   0:b5f04eac9d8f
+     user:        test
+     date:        Thu Jan 01 00:00:00 1970 +0000
+     summary:     initial
+  
+
+Request to clone a single branch is respected in sharing mode
+
+  $ hg --config share.pool=sharebranch clone -b branch1 source1b share-1bbranch1
+  (sharing from new pooled repository b5f04eac9d8f7a6a9fcb070243cccea7dc5ea0c1)
+  adding changesets
+  adding manifests
+  adding file changes
+  added 2 changesets with 2 changes to 1 files
+  updating working directory
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  no changes found
+
+  $ hg -R share-1bbranch1 log -G
+  o  changeset:   1:5f92a6c1a1b1
+  |  branch:      branch1
+  |  tag:         tip
+  |  user:        test
+  |  date:        Thu Jan 01 00:00:00 1970 +0000
+  |  summary:     branch1
+  |
+  @  changeset:   0:b5f04eac9d8f
+     user:        test
+     date:        Thu Jan 01 00:00:00 1970 +0000
+     summary:     initial
+  
+
+  $ hg --config share.pool=sharebranch clone -b branch2 source1b share-1bbranch2
+  (sharing from existing pooled repository b5f04eac9d8f7a6a9fcb070243cccea7dc5ea0c1)
+  updating working directory
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  searching for changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 1 changesets with 1 changes to 1 files (+1 heads)
+
+  $ hg -R share-1bbranch2 log -G
+  o  changeset:   2:6bacf4683960
+  |  branch:      branch2
+  |  tag:         tip
+  |  parent:      0:b5f04eac9d8f
+  |  user:        test
+  |  date:        Thu Jan 01 00:00:00 1970 +0000
+  |  summary:     branch2
+  |
+  | o  changeset:   1:5f92a6c1a1b1
+  |/   branch:      branch1
+  |    user:        test
+  |    date:        Thu Jan 01 00:00:00 1970 +0000
+  |    summary:     branch1
+  |
+  @  changeset:   0:b5f04eac9d8f
+     user:        test
+     date:        Thu Jan 01 00:00:00 1970 +0000
+     summary:     initial
+  
+
+-U is respected in share clone mode
+
+  $ hg --config share.pool=share clone -U source1a share-1anowc
+  (sharing from existing pooled repository b5f04eac9d8f7a6a9fcb070243cccea7dc5ea0c1)
+  searching for changes
+  no changes found
+  adding remote bookmark bookA
+
+  $ ls share-1anowc