The Quadra 840AV surprisingly does not come with a cable for Apple's new AudioVision Monitor. This in itself would be understandable if the monitor came with a working cable, but the cable doesn't plug into any of the 840's ports. Evidently, Apple plans to add the proper port to future 840s, but in the meantime you have to call Apple and order a special cable. Russ Black <email@example.com> posted a note about this on comp.sys.mac.announce and said that Apple charged him for the cable and that their current computerized ordering system didn't even know about it. Apple, you can do better!
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.