Battles' four-man, digitally enhanced factory funk offers a hint (a very loud hint) of what rock 'n' roll will sound like in the 23rd century. Imagine the entrance music at a monster-truck rally starring Optimus Prime—massive drums, double-helixed guitars, otherworldly vocals, something so ridiculously different and brazenly brainy that it makes you laugh out loud. Battles are here and now, but you have to see them to believe it. (Crocodile, 2200 Second Ave, 441-5611. 9 pm, $10 adv/$12 DOS, 21+.)