Call A Bike
Here's another interesting spot by Johnny in Berlin: Call A Bike is a bike rental service where anyone (with a phone) can rent one of these bikes if they come across them. They automatically lock so pesky kids and confused tourists can't just pinch them. The rest of you can simply phone the number printed on the bike with a code (also printed on the bike) and after giving your credit card details, you're given a special code to unlock the bike. Type it in and go. Costs are 7 cents per minute or 15 Euros a day.