Metronome Dance
The act of waving one or two fingers and your head side to side to the rhythm of music, in a metronome-like manner. This dance is usually done by nerds who can't dance or people who just don't feel like getting down. Many nerds who do this dance, usually do it to J-Rock, J-pop, Weird Al, or some other nerdy music such as Banana Phone.
All the nerds in the classroom started to do the Metronome Dance when the teacher turned on some Weird Al Yankovic polka crap.