You can earn $13,000 a year selling your poop

You can donate blood, plasma, eggs, and sperm. Why not poop? Yes, your feces are perhaps your greatest untapped monetary resource. Thanks to a nonprofit organization called OpenBiome, you can cash in to the tune of $13,000 a year -- and save lives while you're at it.

Since 2013, OpenBiome has been processing and shipping loads of it all over the country. The frozen stool is administered to patients who are very sick with infections of a bacteria called C. difficile. The bacteria can cause extreme gastrointestinal distress, leaving some sufferers housebound. Antibiotics often help, but sometimes the bacteria rears back as soon as treatment stops. That leads to a miserable, continuous course of antibiotics.

By introducing healthy fecal matter into the gut of a patient (by way of endoscopy, nasal tubes, or swallowed capsules) doctors can abolish C. difficile for good. Finding a donor is tough business, and some patients grow so desperate that they treat themselves with fecal matter from friends and family. That's what happened to a friend of OpenBiome's founders, inspiring them to open up the first nationwide bank. So far they've shipped about 2,000 treatments to 185 hospitals around the country.

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