Carnac is described as 'A utility to give some insight into how you use your keyboard/'. There are more than 10 alternatives to Carnac for Windows, Mac, Linux and Xfce. The best alternative is Screenkey, which is both free and Open Source. Other great apps like Carnac are KeyCastr (Free, Open Source), Key'n'Stroke (Free, Open Source), Mouseposé (Paid) and Kling (Free, Open Source).
Mouseposé is the indispensible mouse pointer highlighting tool (aka "virtual laserpointer") for everyone doing demos at tradeshows, presentations and trainings, or those individuals with huge and high resolution displays.
A utility to show keyboard keys visually on the Windows screen. - KaustubhPatange/Kling Visually display keys on Windows screen Detect multiple keys and key holds Allow you to change location of display Allow you to change amount of display time
A Little utility that implements a global key logger which displays all shortcuts & keystrokes as you type on screen and with a semi-transparent overlay. This makes it very easy to show any shortcuts you use if you for example record a software demo.
KeyPress OSD is a full-featured screencasting tool for displaying key-presses on Windows. Beyond on-screen keypress display, it features text-expansion, mouse-highlighting and a multi-clipboard manager.