I imagine a brilliant scientist somewhere was thinking of what he could do one day and came up with: I think I'll make a robot that runs on human excrement, then craps into a litter box. And there you have it, the EcoBot-III. Thanks to funding from Bill and Melinda Gates, you know of Microsoft, researchers at Bristol Robotics Laboratory gave EcoBot-III sensors to move itself towards food, water or light which it consumes and then poops out the waste. Like don't stand in the light, swim or smell tasty. Previous versions ran on other bio material like dead flies or sugar which were processed through the MFC or Microbial Fuel Cell which uses e-coli bacteria to turn the bio matter into electricity. The software and sensors monitor the digestive system and can wirelessly report on its surroundings.