A couple of months back there were questions about running Visual Studio.Net using Virtual PC. At that stage the SSCLI was an option for compiling C# code but it was painful to download and there were issues with compiling the source under Panther. Now there is a package available that takes all the hard work out of compiling C# code on your Mac. The Mono project provides an install for Mac OSX. I can't vouch for stability (it's a 0.9 beta) but I have compiled and run Hello World successfully. My main problem was trying to remember the syntax for the boilerplate code that Visual Studio generates automatically. Now I just need BBEdit to add syntax colouring for C# and autocomplete, and I can ask for a Mac at work (just kidding). Seriously this is good news, and not just for students that need to compile C# for school projects. The install is painless and after adding the location of the C# compiler to your path you're good to start compiling. The price of entry is low and Mono has the hallmarks and pedigree to be a significant OS project.