Hi,
New version of a very cool tool called Phalanger was recently released. It is a compiler that compiles your PHP pages/console applications/windows applications to verifiable managed .NET assemblies. You can take your web and run it under Phalanger instead of PHP (which you may completely throw away). You'll get significantly improved performance and you'll be able to easily interoperate with anything else that runs on .NET. This includes being able to directly call all of the huge managed runtime libraries.
It's hosted on CodePlex and it's shared source:
http://www.codeplex.com/Wiki/View.aspx?ProjectName=Phalanger