Missed this year’s Mermaid Parade and Nathan’s Famous Hot Dog Eating Contest? Don’t worry, there’s still another reason to trek all the way out to Coney Island while the says are long. Coming later this month (July 18, to be exact) is the 2009 Siren Festival, the ninth annual indie-rock gathering which brings thousands of androgynous, skinny-jeaned hipsters to Surf Ave. to get drunk on overpriced domestic beer, ride the Cyclone til they puke then strip down to their tighty whities to go wading in the nasty ocean. Oh, and there’s a bunch of free music! This year’s amazing bill is topped by indie mainstays Built to Spill and includes bum-shaking booty dude Spank Rock and local sonic legends A Place To Bury Strangers.