I'm behind Ad Limiter, which limits Google search ads to one per page, picking the best one based on SiteTruth ratings. You can set it for zero search ads if you like. It also puts SiteTruth ratings on Google search results. It's a demo for SiteTruth search spam filtering.
This Mozilla/Chrome add on has a general ad-blocking mechanism inside. Unlike most ad blockers, it's not based on regular expressions looking for specific HTML. It finds URLs known to lead to ads, works outward through the DOM to find the ad boundary, then deletes the ad. So it's relatively insensitive to changes in ad code, and doesn't require much maintenance. The same code processes search results from Google, Bing, Yahoo, Bleeko, DuckDuckGo, and Infoseek. (Coming soon, Yandex support, and better handling of Google ads within ads, where an ad has multiple links.)
So, if I wanted to do a better ad blocker, I could do so easily. Should I? Is another one really needed? Are the headaches of running one worth it?