Triangular Plot Map

http://www.ex-parrot.com/~chris/wwwitter/20050407-it_doesnt_matter_how_you_vote_either_way_your_planet_is_doomed.html

Above is an example of a Triangular Plot map, this map type uses three sides to show comparison between three different values of data.  Above is showing the type of votes and variations between the three types including liberal democrat vote, labour vote, and the conservative vote.