I can blame Jen for leading me to my newest source of continual amusement. TheFunniest.info is a web-based voting project to find the funniest image in the world. The more you vote, the more of the pictures you get to see, and some of them have gotten me laughing pretty hard (some favorites include the monorail cat, the pirate keyboard and "receive bacon"). You can see the current top winners here.
(And by the way, this project is run by the guy who does xkcd, which is itself full of wonderfully funny things.)