I've only ever seen one episode of Psych and that was the one where there whole show were just references to Twin Peaks. Pretty sure it was called Dual Spires. I loved seeing some of the old cast from Twin Peaks in it, made me smile. :> I found it weird though that the guy that played Bobby in Twin Peaks was together with Lana Milford who got around with the town Mayors, haha.

Sadly it didn't make me want to watch the rest of the series.