The Pitchfork Music Festival kicks off its 2008 edition this weekend at Union Park, and we've been highlighting some of the "can't miss" acts of the weekend on Chicagoist over the next few days. Today we'll tackle eight acts from the sold-out Sunday line-up. But before we do, you should know that Saturday and Sunday are completely sold out and there are only a few walk-up tickets that will be available for tomorrow's show. If......