Actually I was thinking of some variation of this, perhaps using some sort of continuous belting.

How long would it have to last? I'm thinking that no challenge would be complete without a goal to achieve. What would be a reasonable goal? One goal would be to ride across the USA on it, but thats a bit of a stretch. Maybe I could ride into town and get a six-pack? That's be about 7 miles round trip. Does that seem reasonable and attainable?