As "The Hangover III" hits theaters, where we're likely to see another Mike Tyson cameo, take a look at some other celebrities who have made memorable cameos on the big screen.

There will never be another "The Hangover." And where "The Hangover, Part II" failed in its attempt to recreate the decadence and debauchery of the first, "The Hangover, Part III" knows its place.