Bender Bending Rodriguez
Futurama is the most consistently hilarious cartoon. Ever. Besides being funny, though, it also has significant mathematical and cryptological content. One of the best Futurama sites out there is La Indoblable Pagina de Bender Bending Rodriguez, named after everyone’s favorite hard-drinking, chain-smoking, extortion ready automaton.
In addition to lots of cool math gags to be found in the TV show and the comic books, the site also gives a nice decryption of three of the alien alphabets that appear in the series. As an added bonus, half of the website is in Spanish, so you will first need to decode that language before you decode the alien language. Oooo, recursion.
As a special bonus, I found at that site a picture of my all-time favorite single sight-gag: