A group called The Open ISES Project (openises.sourceforge.net) created an open source medical dispatch system called Cards 911, a document for use by emergency dispatchers. It gave them a script to follow when an emergency call came in. The answers would lead the dispatcher to different parts of the document using hyperlinks. The entire document was created in OpenOffice Writer. This was a document with hyperlinks in it that helped a dispatcher help the caller as quickly as possible. It was open source and available for free.
Lawyers for a company called Priority Dispatch Corporation sent a legal nastygram listing out ten patents that the company held, which the lawyers implied the Cards 911 project violated. The lawyers demanded that all physical and electronic copies of the documents be destroyed.
Read the full article on TechDirt at http://www.techdirt.com/articles/20090308/0932074028.shtml
Additional information over at WikiLeaks at http://www.wikileaks.org/wiki/Open_Source_emergency_dispatch_OpenISES_destroyed_by_patent_threat%2C_2009