HudCalc is a Mac OS X Heads-Up Display (HUD) Calculator (Calc) designed to remain hovering over all windows while you work.
Have you ever used the built-in Mac OS X Calculator App and was frustrated when it hides behind other windows just when you needed it (except those who have a 27.5” iMac or 30” Cinema Displays where you have more room than you can manage!). HUDCalc will not do that. It is designed to always be on top of all windows and still be translucent so you can see your work. HUDCalc will even stay on top as you move from Space to Space within Mac OS X Snow Leopard. HUDCalc will not stay on top of full screen Apps in OS X Lion. HUDCalc, as a calculator, is designed to perform basic arithmetic (addition, subtraction, multiplication, and division).