I haven't gotten round to talk about this subject yet but when I was in the UK, I picked up a copy of the New Scientist and there was an interesting article about what could be termed open source medicine.
Apparently, a drug used to cure Hepatitis C called interferon-alpha in its pegalated form (see this post for meaning of this) is far too expensive to treat the majority of sufferers as the process of pegalation has been patented by parmaceutical giants Hoffman-La Roche and Schering Plough. The patented version involves attaching the PEG molecule to the surface of the interferon.
So researchers in London decided to find a way to produce a cheap version of the drug allowing far more sufferers to be treated. They discovered a way of inserting a PEG molecule inside the interferon molecule and found it works as well as the drug created with the patented process. Clinical trials are to start in 2008.
The first part of the article is here but you have to subscribe for the full version.