The only thing predictable about TRACY MORGAN (pictured) is that he's unpredictable. He has made a living – which includes seven years on "Saturday Night Live" and the past couple on "30 Rock" – out of having absolutely no filter. It's often a messy affair; his stand-up and TV-promo appearances are the stuff of Internet legend for their rambling, off-color diatribes. Morgan's two alcohol-related arrests, and a complaint from a female disc jockey that he groped her, fuel speculation that his humor isn't always coming from a sober place, but his completely self-unaware delivery makes every joke a suspenseful one. Morgan's also appearing in Ice Cube's latest comedic romp, First Sunday. What will he say next? His two-performance gig Sat., MARCH 8, at Center Stage offers a chance to find out. $38.50. 8 and 10:30 p.m. 1374 W. Peachtree St. 404-885-1365. www.centerstage-atlanta.com.