I often gain graphic inspiration from concert posters. The ones I love the mostest are usually the simplest (I'm not quite sure what that says about me). I've adored the work of the gents over at The Heads of State for years now. I can't get enough of their refined use of two to three colors max or the wood print, hand screened, imperfect feel of all of their stuff. I'm thinking I might just have to buy some prints to adorn my walls. I wish I had a nice long hallway to feature them all.
You can buy prints of many of these posters in their store.