While reading over Scott's list of interview questions (gut-checking that I am at the level I think I am), I came across a really cool tip.  You can find any currently running processes that are using .NET using the command-line:

tasklist /m "mscor*"

For instance, the results running right now on my machine:


Image Name                   PID Modules
========================= ====== =============================================
sqlservr.exe                1292 MSCOREE.DLL
sqlservr.exe                2156 MSCOREE.DLL
devenv.exe                  5708 mscoree.dll, mscorwks.dll, mscorlib.ni.dll,
                                 mscorjit.dll
dexplore.exe                4144 mscoree.dll, mscorwks.dll, mscorlib.ni.dll,
                                 mscorjit.dll, mscorie.dll, mscorld.dll
WebDev.WebServer.EXE        4960 mscoree.dll, mscorwks.dll, mscorlib.ni.dll,
                                 mscorjit.dll
myclickoncedemo.exe         5524 mscoree.dll, mscorwks.dll, mscorlib.ni.dll,
                                 mscorjit.dll