My apologies if someone else has posted about this, but I haven't seen
it before. For those who like this kind of thing -- and who doesn't?
-- here's a story in Wired about a guy who, having decided not to risk
jet-propelled sky diving any more, now fits bicycles with auxiliary
pulse jet engines.

http://blog.wired.com/cars/2008/05/jet-powered-bic.html

--
Paul Turner