Illustration by Ellen Weinstein

We know chocolate fires libidos, improves moods, and makes hearts healthy. Who knew it could fuel cars? In December 2007, British adventurers Andy Pag and John Grimshaw drove from Spain to Timbuktu, Mali, running on biofuel made from factory-discarded chocolate (the trip consumed the equivalent of 80,000 bars) and recycled cooking oil. The two Brits drove a Ford Cargo truck 4,500 miles across the Sahara, avoiding an Al Qaeda shootout and a sandstorm along the way. The highlight of their visit to Timbuktu, Pag says, was finding out about research being done locally on jatropha, a hardy pest- and drought-resistant plant that was recently singled out by Goldman Sachs as one of the world’s most promising sources of biofuel.