If Loudon Wainwright's 1973 novelty hit, "Dead Skunk in the Middle of the Road," is all you know about this talented singer/songwriter, you need to make your way to Oak Cliff for this show. Wainwright's folk songs (and there are a lot of them) can be funny as hell or emotionally devastating. Sometimes they can be both, as evidenced on Wainwright's most recent effort, Older Than My Old Man Now. At 65, Wainwright has lost none of the pathos or dead-on humor that has always been his stock and trade.