You've had some good answers, but i will add that the internet led to a Cambrian explosion of cranks, because now anyone can put up a webpage. There is a catalo

You've had some good answers, but i will add that the internet led to a Cambrian explosion of cranks, because now anyone can put up a webpage. There is a catalogue, although i don't think it's maintained any more: http://www.crank.net/contents.html http://www.crank.net/contents.html