Cormac McCarty, in his recent interview with the Wall Street Journal, commented "anything that doesn't take years of your life and drive you to suicide hardly seems worth doing."
To that end, I bring you (actually Martin Angelov brings you) bike lanes in the sky!
This elegant solution to inherent road conflict is exhilarating. I love how his safety devices are just bike and rider harnesses. It really is just what it looks like, a carnival highwire act presented as a transportation solution. It's a totally legit idea, though. New York had the same idea 99 years ago. Bikes and people are a lot easier and less expensive to vault skyward than automobiles.
Of course there's about a hundred million reasons while we'll never see this particular sky bike lane (here's a couple: what if you get a flat; what if you drop your clif bar or u-lock), but it's definitely thinking in the right direction. Separated bike paths and non-motor networks needn't be earthbound. There's already all kinds of cool pedestrian sky bridges to avoid the cold in Minnesota and Vendetta in Florence, but they don't go very far. Is it possible to develop a raised cyclo-pedestrian infrastructure? It'd be like throwing the subway in the air or building a catwalk for a city.