Most hand held calculators are powered by battery or solar energy, but for those looking for another green alternative, there is now a water powered calculator.
"Just add water or any other electrolytic liquid into its fuel cell and the chemical reaction between its zinc anode and cathode produces an electrical current that will power this Water Calculator for a month before it needs another sip," Computergear.com explains.
These days just about everyone has a cell phone with built in calculator, most people don't even remember the last time they used a regular hand held calculator to crunch numbers, unless of course they're into math or sciences. In order to bring back an electronic device that seems to have lost appeal, the hand-held device offers a unique topic of conversation.
It's great for anyone who likes using old school calculation techniques or gadget freaks who are into green technology, and it's only $19.99 so would make a great gift.