With a brand-new show on Comedy Central and growing legions of worshippers, Sarah Silverman is totally hot shit right now. Tonight she brings her sexy/dorky Jewess-with-a-killer-rack-and-Tourette's shtick to the Showbox. Fans of horrifically incisive wittiness better have tickets already, as the show is sold out. Beg, borrow, or steal a ticket to find out if Ms. Silverman can manage to shock an audience that's hungry for shock. (The Showbox, 1426 First Ave, www.ticketmaster.com. Doors at 6 and 9 pm, 21+.)