RedmondChris writes "A team of scientists from Joseph Fourier University in France have successfully implanted biofuel cells into rats, generating 6.5 microwatts by harnessing the power of glucose. From the article: 'The device uses enzymes to harvest energy from glucose and oxygen found naturally in the body. Past attempts at using such a device in animals have failed because the enzymes have required acidic conditions or were inhibited by charged particles in the fluid surrounding cells. But Philippe Cinquin and his team from Joseph Fourier University in Grenoble, France, overcame these obstacles by confining selected enzymes inside graphite discs that were placed into dialysis bags. Glucose and oxygen flowed into the device, but enzymes stayed in place and catalyzed the oxidation of glucose to generate electrical energy.'"