KentuckyFC writes: The single-celled organism slime mould, or Physarum polycephalum, is an extraordinary creature. It explores its world by extending protoplasmic tubes into its surroundings in search of food and it does this rather well. Various researchers have exploited this process to show how Physarum can find optimal routes between different places and even solve mazes. Now one researcher has worked out how to use these protoplasmic tubes as clock-like electronic oscillators. His experiment was straightforward. He encouraged the growth of protoplasmic tubes between two blobs of agar sitting on electrical contacts. He then measured the resistance of the tubes at various voltages. This turns out to be about 6 megaohms. But the results show something else too: that the resistance oscillates over a period of about 73 seconds. That's due to the tubes contracting as waves of calcium ions pass through them. So altering the period of oscillation should be possible by influencing the production of calcium ions, perhaps using light or biochemistry. Electronic oscillators are significant because they are basic drivers of almost all active electronic devices. But this guy's goal is bigger than this. The plan is to grow a "Physarum chip" that acts as a general purpose computer, a device that will need some kind of oscillator or clock to co-ordinate activity, just as in an ordinary processor, although speed will not be its chief characteristic.