Part fairytale costume party and part concert, this event for KGNU, Boulder's community radio station, sets the electronic sounds of national and local DJs, like Ivy and Scott Everett, to an Emerald Forest decor. Costumes are encouraged--just be sure to wear one that lets you groove, because this all-ages party is really about the dancing. Sat, 8 p.m. Avalon Ballroom, 6185 Arapahoe Road, Boulder, $10