"Offbeat" technical interview questions

I've been looking for some "offbeat" interview questions for developers. In our case, we get developers with excellent technical credentials but we're unsure of their passion, commitment, and social skills. I came up with the following non-standard interview questions and am soliciting additional ones that help gauge commitment, culture fit, etc.



1) What is your favorite third-party library or set of classes to use; why?



2) What's the coolest or most elegant algorithm you've seen; why?



3) Do you have a favorite language for web programming, command-line scripting, desktop apps, etc. and, if so, describe why you like them for those purposes.



4) If you had two weeks to do research in any one area of computer science, which would it be?



5) Have you been in a disfunctional team environment and, if so, could you describe what happened?



If you have some suggestions, please use the comments feature, below. I'd love to hear them.