Among the city's biggest clubs, Ten Fifteen packs for marquee EDM DJs and hip-hop acts like Mos Def. Five dance floors and bars mean you'll lose your posse if you're distracted. Prepare for entry pat-downs; there's a serious no-drugs (or weapons) policy. For a smaller, more laid-back scene, try little-sister club 103 Harriet next door. Sketchy block, but pricey drinks.