CATMaker is an interesting tool for medical text. It helps generate a summary of a case and a "bottom line" assessment.
http://www.cebm.net/index.aspx?o=1216
It's produced by the Center for Evidence Based Based Medicine (CEBM). It might be open source.
Summary tools can be very helpful when used with search engines. They can help give a better summary in a results list, or when used at index time, give the search engine a smaller, more relevant set of text to search over.
