It occurred to me several years ago that with a standardized bed system, a small grower could benefit from a non-motorized, over the bed platform, to attach row markers, seeders, cultivators, mulch layers, and the like. A 2 or 4 wheeled cart with multiple tool bars would be a significant step up from single wheel hoes or the Weedmaster Weed Master vs. "The Pig" vs. "Scuffles". One or perhaps 2 operators could push or pull an advanced cart design. I did manage to assemble a crude device from some rather questionable recycled materials to see if the platform idea had any validity. I have used it to lay drip tape and plastic mulch into pre-dug furrows reliably enough. (2 shovel operators were required to back fill but it seems possible that a set of small discs might suffice) (NOTE: this was on stone free, non-trashy soil) It is useful to layout parallel rows on contoured plots. I did manage to gang mount 2 Earthway seeders. An attempt to attach stirrup hoes was feeble. I need to rework the chassis with better material, then I would like to try scaled down, rolling cultivators on it. (one element of the weedmaster that I disliked was that the implements seemed to be scaled to a garden tractor- kinda klunky). In the design/build stage, inadvertently left until the night before a Commom Ground Country Fair opened, I got some valid advice from bystanders, Eureka moments, some which flew right by me. Wheel height adjustment (preferably on the fly-with a proper throw lever) was one memorable one. So this forum idea intrigues me. In subsequent years, I have pondered how a pedal powered platform might evolve. A couple of ideas from the web currently escape me, so for now DO PLEASE LOOK UP …Kinetic Sculpture Races… Amid some absolutely original artwork are notable geared contraptions powered by people. Finally, look at the Trail Cart (see Google images) for a German designed 4x4. Oh yeah, I'm just discovering now, there's NASA'S Great Moon Buggy Race (see images). I think perhaps the greatest obstacle for people powered units, skepticism, may already have been countered, as I heard Eliot Coleman, pass this idea along at a recent Fair.