via The ASP.NET Capsule #18: Running C# & VB.NET in the same web application – Jose R. Guay Paz.
Great snippet to wack in the web.config file, which allows you to run c# and vb.net code (*spit* 
) in the same web project;
<system.codedom>
<compilers>
<compiler language="c#;cs;csharp" extension=".cs" type="Microsoft.CSharp.CSharpCodeProvider, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" warningLevel="4">
<providerOption name="CompilerVersion" value="v3.5" />
<providerOption name="WarnAsError" value="false" />
</compiler>
<compiler language="vb;vbs;visualbasic;vbscript" extension=".vb" type="Microsoft.VisualBasic.VBCodeProvider, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" warningLevel="4">
<providerOption name="CompilerVersion" value="v3.5" />
<providerOption name="OptionInfer" value="true" />
<providerOption name="WarnAsError" value="false" />
</compiler>
</compilers>
</system.codedom>
