[Haskell-cafe] Bathroom reading

I'm looking for cool but mind-bending examples of functional brilliance. Let us say, hypothetically, you had a bathroom without any reading material. And having read all the Dilbert and Garfield you could seriously stomach, decide you should educate yourself while "on the job". :-) So you decide to print up some "one-liner" style programs into a little booklet. Something between credit-card and postcard sized, with a neat but mind-bending program on it. Don Stewart occasionally swoops in with some fixpoint malarkey to defuse heated discussions. I mean that kind of thing, but with a slightly wider scope than just fibs... Suggestions, please! D.