Pedal-powered saw

ThreePulleys made this effective, if somewhat alarming exercycle cross-cut saw.

It would certianly cut faster if I sharpened the blade properly, at the moment it is no faster than a hand-saw but much less tiring. Adding weight to the blade makes it cut faster but too much weight and it starts to load up the exercycle. Weight at the far end of the blade can make the blade develope a sideways wobble. Weight at the near end worked well when I tried that.