I've always thought that "victual" was a funny word because its spelling and pronunciation are so alien to anything else I know of in the English language. The free dictionary explains the origin of the spelling and pronunciation here:
Usage Note: The modern pronunciation of victual, (vtl), represents an Anglicized pronunciation of the Old French form vitaille, which was borrowed into English in the early 14th century. The modern English spelling reflects the fact that in both French and English the word was sometimes spelled with a c, and later also with a u, under the influence of its Late Latin ancestor victulia, meaning "provisions." The word is now occasionally spelled vittle rather than victual, but in either case the pronunciation is (vtl).
I was curious if there are any other words that have similar "ct", "ctu", or "tu" letter combinations that are pronounced like "tt"?