pedal powered coasters

Since I was curious, I had to do some quick Googling to see what up with roller coasters in japan. And guess what I found? A pedal-powered roller coaster. Check out this article here on the supergreen roller coaster. Although I'm not so sure that roller coasters were burning that much energy to begin with (don't they mostly use gravity once the initial lift is over?), this certainly makes for an interesting idea. Even more interesting was a suggestion made by one of this blog's readers - why can't this be translated into some form of public transportation?

Talk a bout a great concept. You get good exercise, it's green and you get to experience some light thrills in hills and valleys. Although in its current form there appear to be lots of potential safety hazards, I'm sure that with a little ingenuity those could be taken care of. I may just have to toss this idea at my city council...