I said earlier that I couldn't really come up with a favorite, but after some thought, one of them has to be the Aerobics Meltdown.
I still remember someone's phone ringing during a board game session and their ringtone was the National Aerobics Championship Theme. I started bobbing my head to it and I was like 'where do I know that from?' Then it clicked and I pictured that dance routine and started laughing my ass off. The guy whose phone was ringing nodded at me and said "I know, right?!"
Such a good one...