Patrick Dennis is the President and Creative Director of Alliant Studios, a brand strategy and communication design firm in Northern Virginia. He has been a Mac user since 1986, and has enough old Macs in his home to drive his wife to suggest he either "toss them or open a museum." (Feb 2006)
Option-click to Hide Apps Quickly
This trick has been available in the Mac OS for years, but many people still don't know it. If you have too many windows cluttering up your screen, you can hide specific ones easily as you work. When you're in any application, hold down the Option key and click on another app's window, on the Dock, or in the Finder to switch to that other app and simultaneously hide all the windows in the previously current app.