Favit by Favstar.fm brings the funniest tweets to your iPhone
Favit will show you a popular tweet, and the only decision you need to make is whether to give it a star or not. The tweets are all anonymized, unlike on Favstar.fm, which adds the extra element of trying to guess who wrote the joke in question. If you're curious, you can peek, but you have to favorite (or not) first, which removes bias. Favit is a good way to find funny people to follow, and it's also like having a constantly-updated joke book in your pocket. LOL!