To the desperate audiophile strapped for cash, thou shalt not fear: This summer there are free concerts aplenty, featuring names both MTV-friendly and ruthlessly obscure. Just make sure to get there early, to avoid getting shut out (or worse, risk being trampled by a mob). We've selected various shows to look out for, but visit the concert series' websites for full details. Tonight, be sure to check out DJ Brennan Green and Delorean at Stuyvesant Oval's Music on the Oval, or hear Dark Dark Dark provide a live score to the road movie Flood Tide: Remixed at Socrates Sculpture Park!