Ready to tackle a true eco-challenge?  

Can you pack a waste-free lunch for a month? Or limit your web surfing time to one hour each night? Or compost your organic kitchen waste for a month?

If so, you can test your eco-mettle at Carbon Rally, an eco-networking site with earth-friendly challenges for just about anyone.

The site puts up new a Featured Challenge every few weeks, and they promise that most of the challenges are generally small, easy-to-manage tasks.

A current challenge, for instance, is the Ringtone Revival, which challenges people to sell or recycle an old cellphone.

Others include one to stop idling in fast food drive thrus, and go inside to place your order. Or lower your AC thermostat by two degrees — pretty easy to do now that summer is coming to an end.

The site lets you keep track of how much carbon you save. There's also a Total Impact Map that offers an interactive sense of how fast little steps can add up when everyone does their part. There are more than 8,000 people who participate, and they've collectively saved more than 665 tons of carbon dioxide. 

If you've got a competitive streak, Carbon Rally has an array of challenges that you can do as a team. It's also possible to create a brand new challenge (say, to cut back on using the office printer) and involve friends, classmates, and colleagues. 

After all, we all know how to reduce our carbon footprint, and Carbon Rally introduces some group motivation. 

Personally, I think it's a brilliant way to focus on the small steps that ultimately have a clear impact. And the best part? If you play, everyone wins.