My square-wheel bike, on permanent display at Macalester College. This construction, believe it or not, earned me an entry in "Ripley's Believe It or Not"; beats standing in a block of ice for three days or growing three-foot long fingernails. This version is our second such vehicle, built in 2004. The first, from 1995, was a little less refined and the ride on the catenary road less smooth. The new version rides very very smoothly.

Stan Wagon, Prof. of Mathematics and Computer Science, Macalester College, St. Paul, Minnesota

( Img: http://stanwagon.com/)