.net Compact Framework SP1
If you're doing mobile development, this should be of interest:
.NET Compact Framework 2.0 SP1 available for download
Microsoft .NET Compact Framework version 2.0 Service Pack 1 has been released as a download. The service pack was driven by customer feedback and includes stability improvements, new debugging features, extended platform support, and new developer functionality. Most notably, users can install the runtime to removable storage—which especially useful for devices that ship with limited storage space. For more information see the .NET Compact Framework Team Blog.