Did you read the Da Vinci Code? Remember the ambigrams (text art that looks the same when read upside down)? Here are two very cool ambigram websites: http://www.johnlangdon.net/New_Pages/Angels_Demons.htm and http://www.55cards.com/ambigrams/
While we're at it, checkout another type of word play:
Tarzan raised Desi Arnaz' rat.
Damn! I, Agassi, miss again! Mad!
Did I do, O God, did I as I said I'd do? Good, I did!