I am interviewing candidates for a C#/C++ programming position and I just need some ideas for good technical questions to ask to guage someones experience.    I am mostly concerned with C# experience.  Does anyone have some good ideas on questions I should ask?

Questions involving using Sockets and Threading  would be helpful too.

They don't have to be trick questions, but one I thought of was "Name a class that does not have the .ToString() method".