I dont have a massive problem with online advertising, I know content providers need to make money.
That said I did last year install a popup blocker, which gets disabled for sites that Im happy wont spam me with crap. The reg is a good example, 3 tech adverts on this page - I can live with that.
When I open up the local newpapers site and get 15 adverts for "Millionaires in my area wanting to share their secrets" etc thats when I start to get annoyed.
I dont even particularly mind targeted ads, when they work - If I search amazon for something I dont mind If I get adverts for that thing on other sites for a while.