[kps]

And if it's a site I visit more than once, creating a 'display: none' CSS override. Same for the floating headers that break paging, and similar annoyances. (I use the Stylish browser extension.)

[chapium]

For me, sites with intrusive ads and sites i visit more than once are two groups that do not intersect.

[lawl]

That works well until you get to sites that randomize the id/class/whatever of the element or automatically reinsert it once you kill it. At that point i usually look for a different site. Urgh. I wouldn't mind ads if the weren't that fucking annoying.