evolved from Von Dutch's 2 stroke pogo stick, the Hop Rod... dangerous powered pogo

This is the first time I've seen one in person. It looks unused because it probably is virtually unridden. These things have hurt people, and the only riders that I've seen (on youtube) successfully not get thrown have been skateboarders and stunt men

to see Von Dutch's design: http://justacarguy.blogspot.com/2009/12/two-stroke-pogo-stick-and-nitro-roller.html

the Pentrike (might be it's name) of Ed Roth

Found on http://zelastchancegaragedu78.blogspot.com/2010/06/ed-roths.html
I can't find anything else on the internet about it, but if you are interested in another unheard of Roth creation, the "Rubber Ducky" see a full page about it here:
http://www.ratfink.org/roths_rubber_ducky/index.html