We all know cycling is environmentally friendly, but can you go even greener? ReCycle, an L.A.-based start up thinks so. The company builds bikes from 100% recycled aluminum and fits them using only reclaimed materials. For example, the saddles are cork. Additionally, the belt drive is chain free (i.e. no need to oil it up). The idea is a fully sustainable alternative to mass bicycle production. The frame geometry is intriguing too.