Earlier this week, the oil giant ExxonMobil announced a significant shift in direction: Rather than drilling ever downward in an attempt to find more oil, the company will invest heavily in green, growing things that can manufacture biofuel. Exxon plans to put $600 million into the production of algae-based biofuels, and will partner with the genetics company Synthetic Genomics run by genomics pioneer Craig Venter. The announcement came just a week after another industrial giant, Dow Chemical, declared its own investment in algae technology.