"Borboleta is a mobile open source software for primary health homecare - developed by FLOSS Competence Center of IME-USP. The general goal of the Borboleta Project is to investigate tools and innovative methodologies in IT to support home care programs in public health, using advanced tools of Mobile Computing to promote the improvement of health services offered to people with low income."
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iPath is providing a free and open platform for "case based collaboration", especially designed for medical applications (telemedicine, etc). The iPath-Server package provides a sort of medical BBS to discuss/consult cases online. Additional modules are available.