i am a graduate student in an applied math program. we typically get enough math during the day (and night before deadlines). when we party, it's usually just a regular party with food, alcohol, and music - like "everyone else". often the conversation turns to work, because that's common ground.
however, i did through a party on my 10,000th day of life, because anniversaries of birth get boring. (for those of you who don't want to count, that's about twenty-seven and a half years.)