Mono runs Asp.net really well.
You can create websites with Visual web developer and serve them up on a linux box.
C# works really well, you can pretty much copy it right into your linux/apache setup and it will compile.
VB is a work in progress, but if you precompile the VB web app, then it will run just fine.
There is a good tutorial on getting a LAMA (linux - Apache - MySql - ASP.net) server up and running at dotheweb.net:
LAMA: Linux - Apache - MySql - Asp.net - Best of all worlds tutorial
and information about precompiling VB sites with Visual Web Developer:
Visual Web Developer and your Linux server