ViewVC is a browser interface for CVS and Subversion version control repositories.

Trac is a web application which provides issue tracking, timelines and Wiki with Subversion integration. Trac is written in Python and can be either run as a cgi program (any web server) or within mod_python (Apache).

cvs2svn is a cvs to Subversion conversion program.

vss2svn is a Perl script which converts Microsoft Visual SourceSafe (VSS) repositories to Subversion.

Subclipse is an Eclipse plugin.

SVK is a decentralized version control system written in Perl which uses the Subversion filesystem.

TortoiseSVN is a Windows shell extension which adds Subversion information and commands to Windows Explorer.

TortoiseSVN is Subversion for most Windows users. TortoiseSVN brings the full functionality of Subversion into the Windows shell.

There are also some very useful extras. Most notable is the "Repo-Browser" which enables queries and changes to be made directly on the repository.

The project which started this whole business.