Press Windows + R, then type "calc" and enter. That's how you can quickly bring up the calculator application on your Windows computer. This is also the reason many of us do not need a physical calculator around as there's always a PC nearby. But if you are going to have a calculator, here's one worth getting--the 10 Key Calculator created by U.K. designer Sam Hecht, as seen on Boing Boing.
It doesn't really have only 10 keys, but this calculator looks very much like your computer's numeric keypad. You no longer have to bear with the squishy keys on a regular calculator with this. It even has a USB connector so you can use it on a computer screen or, if you'd rather not, you can use the built-in LCD display.
One gripe--the "0" and "+" keys aren't double-sized as they are on a standard keyboard number pad. Also, it's ridiculously expensive at about $88 from Design Museum Shop.
(Source: Crave Asia)