I’m back to my regular update schedule. I was just visiting Macalester College and saw that they had the tricycle pictured below! I have seen pics on the internet of it but didn’t know where it existed.

The original was created in 1997 (and replaced in 2004) by Professor Wagon (not Professor Bike) and rolls smoothly over a road made out of inverted “catenaries”. See a video here for a demonstration.