The most ancient forms of life - bacteria - are exceptionally tiny organisms, yet they have contributed in big ways to our planet. Although long recognized for causing disease, microbes have had a tremendous impact on our survival, and now can help us solve some of our urgent energy problems. Unlike fossil fuels, the microbial production of biofuels represents a new source of energy that can be constantly renewed. Series: "Lawrence Livermore National Lab Science on Saturday" [Science] [Show ID: 26008]