I know that this is how they recover some of the money they pay out, and I don't begrudge them that. I do love this site. However, I find banners as a whole disagreeable, so thusly do I direct you to check this out:
Block Unwanted Parasites with a Hosts File ... if you can see the address of the specific ad that is causing you grief, you could just add that one to your hosts file.
As a side note, I have the entire hosts file from that link included in my system, and I see very few ads while surfing any site.
edited for spelling