Build systems need to do all sorts of things, from updating web sites to deploying databases. Often, the tasks needed to do these things are available, but finding them can be a challenge. I've collected links to various MSBuild task collections that you can plug into your Team Build scripts. Hopefully, you'll find something that helps you get more out of your build.
[UPDATE 5/30/2007] The SDC Tasks Library that was on GotDotNet is now on CodePlex at http://www.codeplex.com/sdctasks.