Biodiesel never ceases to amaze me. Colombian farmers are growing plants for biodiesel on old coca plantations. Mercedes, Honda and others are going to bring high-performance diesels to this country that will be able to run the clean-burning fuel over the next few years.
And now I discover, you can drink it.
Randall von Wedel, a biochemist who has become one of the staunch advocates for biodiesel, points out that it's just vegetable oil with a few molecules removed. It smells a bit like old olive oil and might give you a stomach ache, but it won't kill you. It tastes different depending on what plants or animals the oil was derived from.
Conversely, the similarity to vegetable oil means that, in a pinch, you can pull over your biodiesel car at a grocery store and fill up with a jug of Wesson.
Just to clarify, biodiesel comes from vegetable or animal oils that have been stripped of glycerin molecules. That makes it less viscous. Biodiesel cars and diesel cars are pretty much the same. You may want to change your hoses to accommodate biodiesel but the engines are the same. To run a car on vegetable oil constantly (i.e. not using the occasional jug of Wesson), you should add a heater so the vegetable oil will get viscous. In warm climates, the additional heater isn't necessary.
You can probably drink ethanol, an alcohol made from corn or other substances, and not die as well, but the chances that you'll rob a convenience store afterward go way up.