In the nightlife world, there's no more tragic figure than the hidden bar -- because if it's executed well enough to gain notoriety, the uninitiated'll find it simply by joining the herd of hopeful jackasses loitering outside. For a moving target, check out Temporary Spaces, "volume 1" of which opens with a private event tomorrow. From one of the dudes behind Teddy's, TS is a bar/performance "venue" that plans on setting up shop in one space only to disappear after a couple of months and magically pop up somewhere totally different -- like a toadstool, if toadstools offered a broad selection of vodkas. volume 1's actually a one-time crack den, whose nondescript, newly-painted exterior gives way to a polished, chandelier-bedecked lounge with a PA system loud enough to convince the former tenants Nino Brown's come back to get them. Performances occur two to three times weekly, with acts already booked including occasionally nude avant-gardist Peaches and Franz Ferdinand-ish rockers Moving Units (a phallic rejoinder to TS's nomadic theme). After two months, v1'll close down to open elsewhere as volume 2, meaning that the lone remaining tragic nightlife figure'll be the hopeful jackass admiring the fresh paint job on a newly re-opened crack den.