Ruby + Microsoft.NET= IronRuby
I just saw this today. Ruby is the biggest fad in web development right now. Microsoft, not to be out flanked, has thrown together IronRuby, a .NET implementation of Ruby (released under the MPL license):
IronRuby is a .NET implementation of the Ruby programming language. We are building a high-quality implementation of Ruby, with excellent performance and seamless integration with .NET libraries and infrastructure. We are targeting compatibility with the 1.8.x branch of Ruby modulo continuations.
IronRuby heavily leverages Microsoft’s Dynamic Language Runtime, and both are released with full source code under the Microsoft Permissive License. The IronRuby source code is hosted on Rubyforge, which is a home for open source Ruby projects. We’re looking for contributions to the IronRuby libraries; our goal is to achieve parity with the Ruby standard libraries.
Thankfully, I've decided to pass on that fad.