Perhaps someone could patent the business method of patent trolling. Then sue the trolls for patent infringement.

I suppose this is wishful thinking. No doubt some patent troll company has already patented the idea of suing patent troll companies, and will sue you for infringing their patent if you try to sue them.

Personally I think it would be best to just abolish the entire patent (and copyright) system. But I know how impossibly unlikely that is.