[Brian C. Miller]

This American Life: When Patents Attack! "We take you inside this war, and tell the fascinating story of how an idea enshrined in the US constitution to promote progress and innovation, is now being used to do the opposite."

Added: I once worked for a company that was hit by a patent troll. The company fought the troll and won. However, the company was financially crippled by the cost of defending itself against the patent. It cost more to defend against the patent than what the troll wanted. (The company owner went on the war path because the troll had initially asked for amount X, then later bumped it up to amount Y.) One thing to note about having your patent found invalid: you have to pay back all previous settlements. So in this case the troll was down a very deep well, because he had hit up a number of companies previously. (The patent was invalid due to it being misfiled, and the judge also commented that he had never seen so much prior art presented.)