For all you hard-core nerds out there who just can't leave the unmanaged world behind, check out some of these resources:
The Microsoft Win32 to Microsoft .NET Framework API Map article identifies the Microsoft .NET Framework version 1.0 or 1.1 APIs that provide similar functionality to Microsoft Win32 functions.
The PINVOKE.NET website attempts to address the difficulty of calling Win32 or other unmanaged APIs in managed code by providing all the PInvoke message signatures for you.
And here is a nice diagram that shows how PInvoke works.
