MSDN Mag has an interesting article on tools that convert code from c# to vb.net and vice-versa. I have come across a number of clients and developers both in the company I work for and also at clients who are interested in this. I find this whole topic quite intriguing, especially since in .NET there are minimal differences between c# and vb.net, at least if you stick to only managed code. Also it is quite easy to reuse functionality between the various objects (especially in these days of SOA - more on that some other day). This of course is easier if your are not trying to reuse WinForm apps. Irrespective, there is a lot of demand and some of the options listed here allows you to download the code and play with that too.
- Kamal Patel’s C# to VB.NET has a ASP.NET app and also a WinForm - http://tinyurl.com/68pav
- #develop IDE, open source IDE that has an inbuilt conversion tool - http://tinyurl.com/5lnbk
- VB Project to C# Project Tool - http://tinyurl.com/6sra9 . This internally uses the #develop translation engine so make sure you download that and build it.
For more information you can read the MSDN article here .