There is a significant effort going on in building a completely free (in the sense of open source) software platform for medical use. Below you find links to websites with further information on the projects.
Freie Software für die Medizin - http://www.openmed.org
Gnumed - A Free Project for Paperless General Practice - http://www.gnumed.org/
Drugref - Free Peer Reviewed Pharmaceutical Reference - http://www.drugref.org/
Debian-Med - http://www.debian.org/devel/debian-med/
News resource: http://www.linuxmednews.com
JOSMC - Journal of Open Source Medical Computing - http://www.josmc.org/
In the news:
The OpenScience Project pursuites a similar goal in the sciences.