The Electronic Frontier Foundation (EFF) is asking the Internet community to let their elected representatives in Washington D.C. know that they support H.R. 845, better known as the SHIELD Act (check it out here (PDF)). What is the SHIELD Act? "SHIELD" stands for "Saving High-Tech Innovators from Egregious Legal Disputes."
The bill sponsored by Rep. Peter DeFazio and Rep. Jason Chaffetz would make it so those companies and law firms that are engaging in patent trolling in U.S. courts would be forced to pay the court costs of companies and individuals they sue if they lose (because the patent is found to be invalid or there is no infringement).
While the law would not stop all patent trolling cases it would certainly make law firms that engage in them think twice before targeting someone with litigation. It would also give those accused of violating a patent the breathing room needed to defend themselves in court if they have to.
If you'd like to see the activities of patent trolls severely curtailed, this is a good way to do it. You can contact your representative via this handy dandy EFF page.