I just finished a Web-based C# to VB.NET converter for .NET 2.0. It took me about half an hour and 20 lines of code. How come? Well, Daniel (#develop 2.0 PM) did a video on NRefactory, which is at the heart of #develop's parsing infrastructure. I took some of his demo code plus some of #develop's internal code converter, and put it into a ASP.NET 2.0 page. Presto, that easy if you can stand on the shoulders of giants.

Oh, and I actually put it online, here is the link: C# to VB.NET converter (you can find the source code for a simpler VB.NET implementation of the converter here).