The European Commission has come up with something for the eco-warrior on the go: a cell phone application that tracks one’s own carbon footprint. After downloading the free program (at mobgas.jrc.it), consumers can use their mobiles as an eco-diary, recording, say, time spent driving and watching TV. The program calculates how much greenhouse gas their activities are creating. If they upload the data to the site, users can see their footprints ranked against national and global averages. The mobGAS software was launched to coincide with the round of U.N.-led climate talks that just concluded in Bali. It’s available in 21 languages and is accessible to anyone with cell-phone Internet access.