Seconded. I use this along with NoScript, SelfDestructingCookies, and Adblock Edge (an ABP fork without any "acceptable ads" feature).

A lot of the time it's a big pain to get it working right (say, to watch a video on a news site), but that's simply the price I have to pay in today's web to retain at least a bit of privacy and security.

If anyone wants to make a neat extension, it seems like all these extensions could be combined into one with a slightly better user interface. If you want to make it really spiffy, the black/white listing for these could be shared in a distributed hash table with some sort of voting/trust mechanism.