SuperF4 closes the foreground program when you press Ctrl+Alt+F4, different from when you press Alt+F4 which merely asks the foreground program to exit, allowing it to decide for itself what to do. You can also shutdown a process by pressing Win+F4 and then clicking the window with your mouse, which also allows you to press escape or the right mouse button to exit this mode without killing a program. SuperF4 is able to close all kinds of processes, whether they are hung or not; a very effective tool for regaining control of your computer. Source code can be viewed here: http://superf4.googlecode.com/svn/