I do not want to ask candidates questions, but rather give them several problems to resolve. The reason for this is that I've seen people be excellent with theory, but when confronted by a real world c# issue, just couldn't hack it.
These c# problems should be simple enough that it won't take more than 5-20 minutes to resolve, yet complicated enough that I'd be able to weed out candidates that can't code.
Right now, I typically ask the applications to reverse a string and remove duplicates from a List. This alone weeds out a large number of people.
Any other examples I could use?