Buildbot

For one of my projects I've been using Buildbot for quite some time already. So far it satisfies all my needs in distributed builds of my continues integration process. Here you can check the web interface of the builds out.
Well, Buildbot very simple in installation and configuration, supports SVN and, what is very important, it supports distributed builds. Check out my configuration file (master.cfg) and my custom css.
A summery of the Features Buildbot 0.7.6 provides:

• run builds on a variety of slave platforms
• arbitrary build process: handles projects using C, Python, whatever
• minimal host requirements: python and Twisted
• slaves can be behind a firewall if they can still do checkout
• status delivery through web page, email, IRC, other protocols
• track builds in progress, provide estimated completion time
• flexible configuration by subclassing generic build process classes
• debug tools to force a new build, submit fake Changes, query slave status
• released under the GPL