We support every effort to go green, from recycling, composting, green building design, hybrid cars and, of course, those funny-looking lightbulbs that don't work.

But quite possibly our favorite planet-saving effort ever is the policy implemented by Regina Goetz, a former sex worker and current madam at Maison d'Envie, who has hit upon the idea of offering discounts to Johns who arrive by bike.

It seems times are tough even in the usually recession-proof hooking industry, so, to prevent her girls from being, ahem, laid off, Regina implemented the Green Discount for randy gents who arrived via pedal power. The discount amounts to five euros off the already incredibly low, low price of 25 euros for 15 minutes of dirty, dirty German sex.

To qualify for the discount, clients must show their helmets or padlock keys, or hand in their bus passes. "The environment is a topic on everyone's lips, and it's pretty difficult to park around here. So we came up with the idea of an 'eco discount' of five euros to anyone who leaves the car at home," Goetz told AFP.

Save the petrol, save the earth and save a hooker's job, too. It's win-win-win!