Via the BCS:
Nearly three quarters – 73 per cent – of internet users clicked away from a favourite website because of an annoying advert, according to research.
The survey, carried out by Opinion Matters for HowTo.tv, also revealed that 59 per cent no longer visited a particular website because of its advertising.
I use AdBlock for a serene and calm web experience, so when I use someone else's computer I'm always amazed at the sheer level of noise on the web and the crappiness of pages plastered with ads.
I was using Add-Art in conjunction with AdBlock, and will again when it support Firefox 3 because it's a lovely idea. If you haven't heard of Add-Art before, check out this Webmonkey article until you can install it on Firefox 3.