I happen to love Tom Swifties and Sarah Swifties, mostly because the pun comes at the very end of the joke, so the unsuspecting tester of your joke is left with an odd look on his or her face (until he/she gets it). Swifties are sentences in which adverbs (most often) relate to a word or phrase both properly and in a pun, as in the following:
For more fun with Swifties, see chapter 4 of WordPlay Café. Enjoy!