An interesting article in Scientific American discusses several uses for algae, one being its use as a food source. Where others have searched for an algae that can produce large quantities with few inputs, no one has found it yet. The scientist in this article discusses genetically modifying algae in order to create the algae desired and achieve the necessary outputs. His hope is to create algae that might provide not only food, but also fuel while also helping to combat Carbon Dioxide content in the atmosphere. See more on the subject here.