Mercurial

Bitbucket
Mercurial hosting.
http://www.bitbucket.org/

Distributed revision control with Mercurial
An unofficial manual for Mercurial.
http://hgbook.red-bean.com/

Eclipse plugin
Mercurial plugin for Eclipse IDE.
http://trac-hg.assembla.com/mercurialeclipse

freeHg
Mercurial hosting.
http://freehg.org/

hgsvn
A set of scripts to work locally on Subversion checkouts using Mercurial.
http://pypi.python.org/pypi/hgsvn/

NetBeans plugin
Mercurial plugin for NetBeans.
http://wiki.netbeans.org/MercurialVersionControl

TortoiseHg
A shell extension that let users of Mercurial SCM (Hg) work directly from MS-Windows Explorer.
http://tortoisehg.sourceforge.net/

TracMercurial
Mercurial plugin for Trac.
http://trac.edgewall.org/wiki/TracMercurial