Some summaries of the history, categories and context of New Energy inventions by inventor Peter Lindemann and Patrick Kelly:
http://www.free-energy.ws/lindemann-1.html
http://www.free-energy-info.co.uk/

A site covering all sorts of developments in the alternative energy field curated by Sterling Allan and the New Energy Congress:
http://peswiki.com/index.php/Main_Page

Their regularly updated “Top 5 Exotic Free Energy Technologies” list:
http://Top5Energy.com