Turning corn into ethanol to be used as fuel - instead of moonshine - isn't anything new. It has, however, only replaced about 3% of our fuel consumption. But scientists are working on a new twist to turn corn stalks and other waste products such as "wood chips, sawdust, wheat straw, [and] waste paper" into liquid fuels. Estimates are that the U.S. could replace as much as 30% of its fuel usage with fuel made from biomass.

The basic process is to take a ton of biomass (essentially plant waste left over from food crops) and throw it into a hopper with some enzymes. The enzymes break apart the fiber in the biomass and turn it into sugars, which can then by fermented and distilled into pure, 200-proof ethanol. It will take a lot of innovation and some large scale plants before it really starts to prove itself, but the thought that we could run a third of our nation on leftover junk is pretty amazing.

(H/T Cranach)
Forgive the categorization, as its not exactly biodiesel, but it is close enough.