I was contacted by a recruiter after submitting my resume at a campus event. First, there was a phone screen by an HR person going through some semi-technical and trivia questions compiled by somebody else. These were pretty easy, and the interviewer probably just tried to determine whether your answer came close to what was listed on their sheet. Then I had a second phone interview with a more technical person. Again, there were some light trivia questions of the sort other posters have listed already and a coding question. The third one was over Skype and consisted of two back-to-back interviewers with engineers. One of them had trouble remembering one of his coding questions, so afterwards I found out he hadn't formulated it quite right. This was a bit confusing to me on the spot and might have contributed to less than stellar performance.

Maximum subarray problem.