In its fourth year, Carousel Festival continues to celebrate the DIY side of the local music scene with three days of music packed into a variety of off-the-beaten-path venues. Dozens of bands are playing, but don't miss the Pica Beats on Friday, Helms Alee tonight, or the spooky and raucous Feral Children and the childlike-voiced singer-songwriter Whitney Ballen on Sunday. (Aug 28–30, www.myspace.com/carouselfestival. Three-day pass $17/one-day pass $8/individual shows $5, all ages.)