Crispin Porter & Bogusky invite you to read and write "secret messages" in the hitherto under-utilized medium of Jell-O. "Jigglevision" lets you craft secret messages and "disguise them" in Jigglevision patterns, using a special site. 

To reveal the message, you need to spend some money and actually buy a snack-sized Jell-O, peel off the lid, and look at the pattern through the top of the cup.