When you mutter out the phrase flash mob there are only a couple places a persons mind will go, if you are a photographer will got to a mob of people with camera flash. I have been to a couple of events run by Jesse Willesee in the past, which used to go under the name of 700 photos but has now changed to his flash mob.
The all go down a similar path. They partner with a hotel and let some super talented designers go nuts creating a theme for each room, add some beautiful (and handsome) models then invite as many people with cameras as possible bribing them with cheap or free drinks if need be. While they are generally quite packed, hot and sweaty they are generally a lot of fun and you can walk away with one shot that you love.