Posted Nov 27th 2006 10:49AM by Sam AbuelsamidAs part of the Los Angeles Design Challenge that goes along with next week's Los Angeles Auto Show, a group of designers from GM has created the Hummer O2. Right now this green Hummer is only a set of drawings and will probably never be built, but it's an interesting idea. The body panels are filled with algae that turn absorb carbon dioxide and release oxygen. Since algae only has a limited life span, it would seem like it would have to be replenished periodically, If you've ever cleaned out pond or fountain, you know the algae can get pretty messy, so this might not be a very practical proposal. But at least people are thinking about it.