The Oxford Electric Bell is an electric bell housed at the Oxford University Claredon Laboratory that has been quietly running on the same dry pile electric battery for 175 years, for a total of around 10 billion rings. Contrary to some reports, the long-running battery does not constitute perpetual motion.
Some published reports of the Pile unfortunately refer to it as an example of perpetual motion but the Guinness Book of Records has it under the “worlds most durable battery” delivering “ceaseless tintinnabulation”.
images via Wikipedia
via Vice Motherboard