If hours of dancing to mid-tempo bass-heavy hip-hop sounds as supremely satisfying to you as scoring a parking spot in downtown Oakland during First Fridays, then clear your schedule for the monthly Booty Bassment at The Knockout (3223 Mission St., San Francisco). True to its name, this second-Saturday party, featuring DJs Dimitri Dickinson and Ryan Poulsen, mixes classic and new hits from the likes of Too $hort and 2 Chainz, all for the goal of inducing mass rump-shaking. But unlike other parties, Booty Bassment manages to avoid being a total gropefest, so you can twerk, yike, and dip with abandon. Best of all, this gluteus festivity only costs $5, which is cheaper than Hipline, Zumba, or other dance workouts. Prepare your backside.