Next time you're in Hamburg or Berlin
...save some serious money on a rental car. Rent a Maxhopp car for one Euro/day (about $1.10). Get an environmentally friendly car for exactly three days and agree to drive at least 30 km/day. What's the catch? There isn't one. Maxhopp vehicles are plastered with advertisements -- you drive 'em around, you get 'em dirt cheap. Now THAT's cool.
Maxhopp | Rent a car for a euro a day