In high school, entrance to a classier crowd was simply a matter of taking out your angry lip-ring and buying a shirt that didn't reek of loneliness. To see how a bar pulls this switcharoo, hit 800 Larkin. Formerly the divey O'Farrell Street Bar, 800's longtime owner has ushered out the sports nuts and off-duty strippers to make room for a 30ft mahogany bar, plush leather armchairs and couches, and a new, gray-felt pool table whose cues yearn for chalk instead of condoms. The ramped-up beverages include 12 taps, Veuve and Dom by the bottle, and new signature cocktails like the Slippery Fish (dark rum, oj, lime juice, ginger beer) and the Red Rocket (citrus vodka, triple sec, grapefruit/raspberry liquor, aroused golden retriever). There'll also be a weekday 2-for-1 beer happy hour (5-7pm), and on weekends, gargantuan $3 bloodies -- thereby ensuring the fun doesn't go the way of the grime, and you never see the inside of a Bed Bath & Beyond again. The owner's not completely shutting out her old pals: stop by for a drink or seven, and she'll hand you a $10 discount pass to the nearby New Century stripclub -- just remember to change your shirt afterwards, or you'll no longer fit in with the in-crowd that is your girlfriend.