This is an easy to use calculator.
You can start it by pressing F12.
+ - * / ^ %
Addition: 12.34 + 8.8 =
Power: -5.3 ^ 2 =
Percent: 2.2 * 125 %
F1 - opens help window
Esc - clears the screen
F11 / F12 - changes the opacity
(Alt + F4) - Exit the calculator
I wrote this calculator because I lost mine hardware one. (I found it three days later on the desk!!!) Never mind, this piece of software is very useful if you want to remember something like some price or phone number. And surprisingly it calculates pretty well.