Since we’re talking about urban bike-sharing today, it’s worth taking a quick look at Germany’s Call-a-Bike program. The remarkable thing about this system is that you don’t even need to leave the bicycles in a set parking spot. Using your cell phone you call the phone number on the side of the bike, a magic ray beam shoots out of the sky an unlocks the bicycle’s rear wheel (I may not have the technological details correct there), and when you’re done riding you call the number to close your transaction and leave the bike standing at any street corner in the city. It costs 6 cents per minute. Call-a-Bike is run by the Die Bahn, the German national transportation agency.

Photos: Aaron Naparstek, Berlin, March 2004