MonoDevelop is the IDE for the Novell Mono project. It was initially created as a fork of #develop.

It has its own site at  http://www.monodevelop.com/

You can download preview builds at  http://monodevelop.com/files/MacOSX/trunk-builds/

(2009-12-03) For Mac Users, consider getting MonoDevelop at  http://monodevelop.com/Download/Mac_MonoTouch which reports itself as an RC. For some reason, the MonoDevelop page is offering Beta 2 instead the RC.