700 bicycle riders on fixies, single speeds, track bikes, and just plain old mountain bikes, cruisers, road bikes, and special one-of-a-kind self-created bikes. They are out for a little ride in the night. For all of the apparent confusion, there are leaders, and there is organization. Those who organize pick roads, bring music, create themes, and find places to stop and hang for a while to dance, do stunts and tricks, and exhibit ever manner of strange behavior. All of it in the name of a …