First, there is the letter of Cecil D. Quillen, Jr. whose efforts on behalf of patent reform we have mentioned here before. Needless to say, despite the thoughtful comments he has received little response.
Next, Salvatore Modica send us this link to an article documenting how patents on the human genome have reduced research in the area. There is a message here, especially for people like Andrew Sullivan who exaggerate the role of pharmaceutical companies in saving their lives.
Finally I'd like to draw attention to the excellent paper of Bessen and Nuvolari in which they nail the reason for widespread knowledge sharing: the existence of a competing existing technology.