This Hydro Powered Calculator combines electrodes, alloys and a mysterious new chemical and manages to create electricity in the process. Not only that, you can use said power to calculate things, like the mortgage arrears, tax bill or your chances of meeting Angelina Jolie next Tuesday down the chippie. (hint: slim). $10.99.
The water-powered batteries consists of two electrodes made of special alloys, which, when immersed in water, produce electricity through a chemical reaction. Simply refill the battery as the water evaporates, typically every two to three months. Not only is this eco-friendly, it’s providing free energy. Well, not enough free energy to power your computer or drive you home, but it’s still impressive!