MS.NET: VB.NET or C#

[katcode]

I vote either Whitespace or Brainfuck.

I'd say port it to Ook! since any monkey can understand it. ;D

Also in my opinion i'd stay away from .NET and Mono especially. I dont like Relying on a Framework for my Applications. (Except SDL since SDL is ftw)
Really, FreeBASIC is way faster than .NET

(and since its based on QBASIC same as VB is then it's easier to port, Also Linux support ftw.)