A Youtube recruiter somehow obtained my resume and called me up to schedule a phone interview. The phone interview went quite smoothly - it consisted of a few background questions, some broad technical questions, and some more specific programming questions. For the last part, we used a shared GoogleDoc, such that I was able to type out my answers. I was flown out to the Youtube campus (they paid) and put up in a really nice hotel with a group of ~30 total candidates (for what it's worth, 90% of these were graduate students). We had a day-long group tour, including four 1-on-1 interviews, finishing with a dinner at a 5-star hotel restaurant. The 1-on-1 interviews all had at least one technical question, but the rest of the content varied depending on the interviewer. Some asked questions about spam prevention, others about memory allocation. There were no questions like "how many pennies can you stack end-to-end to the moon?" It's been almost a year, so I can't remember too many specific questions.