Adblock gives us the internet as it 'should' be Rated 5 out of 5 stars
Every time I set up Firefox on a new machine, either for myself or a friend, this is always the first extension I install.
If I was limited to one add-on, this would be the one I'd choose.
I had to use IE7 last week, I had to experience the internet without Adblock -- nightmare! So much garbage now on the 'net, it's bad as watching commercial television. Maybe worse. A horror show.
I've been using Adblock for years and expect to use it for years more.