Via boing boing, this delightful tale of a wiseacre who bent the brains of some state employees by testing the limits of what he could pass off in place of normal payment for his $1 toll (say, two pictures of rapper Fifty Cent. or an array of not-explicitly-banned foreign currency). tee hee
Update: also worth checking out are his experiments with varying his signature on credit card slips -- not just the style, but the language (pictographs?), the name, and more . . .