My friends left on a Tuesday. When they left I was in 82nd place for all of NY on foursquare for the week. Like I said, I'm a nerd... but being in the top 100 was something I'd never accomplished & NY is massive with tons going on (goes without saying), and foursquare was originally developed in & for NYC so the userbase is pretty solid. I got a massive geek high when I saw that.