One more for focused comedy blogs

Passive Aggressive Notes - a site dedicated to nasty notes that people write for one another anonymously and leave in shared spaces.

You know how every once in a while when some fool cuts you off in the parking lot, you have the urge to write a nasty note and clip it to their windshield after they park? Well, if you do that sort of thing, your note is probably on this blog somewhere.

Like Cake Wrecks, they're very focused and have piles of material. They have so much material in fact, they can do an entire series devoted to notes left for people who stole cheese.

In the words of JWZ, "Oh Internets, is there anything you can't do?"