What instrument is this one?

Are you sure its an instrument . lol

I know that they play music and that they use that thing for something, but dunno what it is

What band is it? I wonder if it’s like Modest Mouse, where the tracks are engineered.

an alcohol meter?

It’s Electronic Music, band name: Nortec Bostich+Fussible, here’s a video http://www.youtube.com/watch?v=4zYaCGEtFDU 0m36s you can see how they use the “instrument”

Its a synth controller, similar to the effects pedal with a guitar. It allows him to control the synth from his hands as opposed to being at the keyboard playing. The Nortec Collective Use instruments and then modify the sounds using the little controller he had

Another little thing is that on the photo you linked, you can see the cord going into the keyboard -> computer. This means it is most likely a midi controller for some digital music maker.

It’s a cheering and clapping simulator. Used by the performer when nobody shows up for the concert.

@SirGoofy don’t insult the Nortec Collective, they’re awesome!

Don’t know what it is, but I want one!