This clock, created by Dutch designer Marieke Staps is soil-powered!
“The clock works with copper and zinc electrodes that plug into the soil. The soil functions as an electrolyte, or conductive medium through which an electrical charge can flow. The natural metabolism of biological life produces enough electricity to keep the clock working. The trick? One has to remember to water the plants in order for the clock to keep working. The principle is quite poignant, keep the plant alive and time continues.”