(NUTTY POST-ROCK) Need New Body's latest album, Where's Black Ben?, comes as a slight disappointment after their two previous blurts of musical mutations. But disregard that, because in the flesh these Philadelphia freaks bust out circuitous, rambunctious compositions like Frank Zappa's '70s groups reincarnated, and burnish their mongrelized wonkery with Fugs-like irreverence. NNB could do a 40-minute homage to The Faust Tapes or belch the Bulgarian national anthem, and I wouldn't be surprised either way. (Crocodile, 2200 Second Ave, 441-5611. 9 pm, $8, 21+.) DAVE SEGAL