Have you ever been typing and you know the word you want to relay, but aren't sure how to spell it? Try this... start typing the word (the more you know the better), and then press F5, and you will see several options. Simply click on the word you want, and then it will complete it for you. This only works in OSX Cocoa Apps... Safari, Mail, Textedit, etc... pretty much most of the apps you use. Bonus: Don't have an F5 key, press COMMAND - ESCAPE -- it does the same thing... if you don't have Front Row installed. And if you do.. you can disable the keyboard shortcut to launch it it via the System Preferences -> Keyboard & Mouse - > Keyboard Shortcuts. Notebook users: To activate the F5 key, you will need to hold down 'FN' when you press F5, or it will only change the volume.