Basically, it would be a non profit organization that accepts donations of patents by hackers, and uses them to sue only companies that themselves have used patents offensively.
Blatant patent trolls could also become targeted for life at future businesses - although I'm not sure of the legality of this - to serve as a severe disincentive for this kind of behavior.
Although it might take a while and quite a bit of money to get started, it seems like it would fund itself indefinitely once going, and enough people seem to be pissed off enough about the current situation that a serious amount of brainpower could be donated to the project.
Does anyone see any showstoppers for something like this, or is it just a matter of not having someone benevolent and gutsy enough to pull it off?