Free hosting of Mercurial repositories
Here are some places that provide free Mercurial hosting:
Alioth (Debian's GForge instance) supports Mercurial and the repositories are accessible via hgweb.
BerliOS Developer supports Mercurial and the repositories are accessible via hgweb.
Bitbucket Github-like hosting service for Mercurial. Includes bug tracker and wiki. Paid plans also available.
Codebase - Offers a free plan for small sized Repositories (Mercurial, Git and Subversion). Polished web interface. SSH and HTTP.
Google Code Supports svn and hg.
Firefly supports Mercurial. Its free plan offers 1 public repository and 200MB storage. Paid plans available.
Intuxication (repository index) - free Mercurial hosting
KForge (Knowledgeforge.net service using KForge) A full-featured self-hosted project management solution with integrated support for svn, mercurial and git repositories.
Kiln provides Mercurial hosting, code review, and bug tracking, and is free for up two developers.
Mozdev provides free project hosting for Mozilla applications and extensions.
Project Kenai An integrated suite of collaboration services for developers to freely host their open source projects and code.
Savannah, the software forge for people committed to Free Software, supports Mercurial and the repositories are accessible via hgweb.
ShareSource.org - A Sourceforge-like server for hosting projects. Supports Mercurial out of the box
SourceForge.net - The most popular hosting service for open-source developers now also officially supports Mercurial (since 11.03.2009)
SSHControl.com - Hosting for Mercurial, Git, and Subversion over SSH. Free hosting for small projects, two paid levels at $4.75/mo and $9.75/mo.
XP-Dev.com provides Mercurial hosting, project tracking and integration with various other project/issue tracking tools.
It is planned to offer free hosting on hgserve.org.
Historical, now unavailable
freeHg (repository index) - simple postmodern developer-centric hosting (HowToSetupFreeHg)
as of 20090201, freehg.org seems to be down (see http://stackoverflow.com/questions/95977/bitbucket-or-freehg/677254#677254)
Hosting your own repositories
See PublishingRepositories for more information on how you can host your own repositories and provide web-based repository viewing.