How to setup a .NET Development Tree
NAnt is a free .NET build tool. In theory it is kind of like make without make's wrinkles. In practice it's a lot like Ant.
CruiseControl.NET is an Automated Continuous Integration server, implemented using the Microsoft .NET Framework.
L Sharp .NET is a powerful Lisp-based scripting language for .NET. It uses a Lisp dialect similar to Arc but tightly integrates with the .NET Framework which provides a rich set of libraries.
L Sharp is free software distributed under the terms of the GNU General Public License. You can download the latest release from Sourceforge. You may also want to read Rob Blackwell's Web Log