Moshing
Moshing is a type of dance characterized by audience members aggressively pushing or slamming into each other. It is frequently if not invariably accompanied by stage diving, crowd surfing and headbanging. It is commonly associated with punk, hardcore, and metal music genres, but has expanded into more popular rock genres as well. Moshing has been described as "one of the most energetic, crazed, communal forms of dancing ever invented". While moshing is occasionally done to recorded music, it is far more prevalent at live shows.
Today, many variations of moshing exist, such as "thrash", and the dance is practiced at concerts of many musical genres. Moshing is typically done in a mosh pit or circle pit. There is a loosely acknowledged "moshing etiquette", which involves immediately helping up others who fall down and holding up lost articles of clothing (usually shoes and hats) to be claimed by their owners.
Aahh, I love Wikipedia's description of moshing lol, they make it sound like an art form don't they! :)
Seriously though, you can't beat a fucking good mosh when your at a gig!