A lot of people were talking to me on the weekend about Izhar Gafni and his cardboard bicycle.
I posted a comment about it last week, but if you missed that, take the time to check out the No Camels website and the six-minute video on this (mostly) cardboard bicycle.
Belt-driven, reinforced cardboard frame and wheels (with rubber applied to the outside of the rims) and designed to be produced at a cost of between $9 and $12 a unit, it is accessible transportation for anyone.
Although, you can pick up a steel frame bike from almost any suburban street on garbage day and refurb it. It'll cost you more than $10, but it, too, will be cheap dependable transport.
Still, having a cardboard bike is a talking point.