Adblock plus, the adblock extension for Firefox, makes a case for themselves in their anatomy of ads.
Personally I very rarely use a browser without adblock installed on it, and when I do (or use something that's not Firefox) I always have a feeling of "oh gads, is this what normal people have to deal with?" I realize I'm stealing from the pockets of web developers and the little guy (hey, I run google adsense on this site, and notice a decrease in the meager return I get from it over the last year or so (hint hint)), but the arms race of the advertisers adding more and more ads to pages has just made a non-adblocked Internet unbearable.
Sidenote: please support the sponsors of UFies.org :)