I'd heard about Bike Party before and wanted to go but didn't get around to it. Finally, Jess went and had a blast. So I finally added the Bike Party website to my RSS reader and made sure to show up.
It's a total happy mish-mash of different cyclists. I took the VTA there with an older guy with a family who cyclecommutes and works for the postal service. There were folks of all ages and looks. There were tandems, xtracycles, fixies, roadies, mountain bikes, cruisers, art bikes, choppers, and other crazy things. There was a tandem dragging a couch with a stereo system built in. There were glowsticks and blinkies and bike lights.
It was crazy. Totally crazy. The mass even grew as people who were out on a ride of their own joined up. Also, unlike Critical Mass and like LA's finest cyclists, the Midnight Ridazz, Bike Party has organizers. Which means that some effort was made to curb more destructive elements of the ride. So we stopped at red lights (mostly) and tried to obey the traffic laws.