Business Week has a viewpoint article, written by a former scientist (who owns some 70 patents) and current VC, about how the current US patent system is hurting innovation. According to Greg Blonder:
The patent system was designed to encourage the free flow of ideas, in exchange for a temporary monopoly. Not all ideas, however, are worth pursuing, worth defending, or worth backing financially. And this gets to what, at bottom, is wrong with the patent system: We issue patents too easily for trivial ideas, thus diminishing protection for true breakthrough ideas.