for the Star Wars lovers...
How about this one?
(and YES she is 18. I know because I know where she keeps her poor, sore-backed horse)
So the Bear Calvary poster is my background on my computer screen. Today, a friend of mine borrowed my computer to give a joint lab presentation. He powered it up and the room full of professors and Chinese post-docs was greeted by the line "Yeah, you're pretty much fvcked" - somehow, they were not motivated.