These are magic Mac keystrokes and other shortcuts;
Screen capture - CMD-CNTRL-SHIFT-4 captures an area of the screen to the clipboard for pasting or whatever. Here's the URL for a more complete discussion. Screen captures
Force Quit - CMD-OPTION-ESCAPE allows closing of locked up programs. Can also be done from the bottom menu by CNTRL-clicking the icon
Mac freeware source - http://opensourcemac.org/
