MODE32 users should be absolutely certain to install the new MODE32 version 7.5 from Connectix (see TidBITS-243) before upgrading to System 7.5. We have it on good authority that installing System 7.5 on a non-32-bit-clean Macintosh with an earlier copy of MODE32 (or perhaps Apple's 32-bit Enabler) may cause severe damage to the system software, necessitating a complete reinstallation. Also, MODE32 7.5 is compatible with System 7.1, should you not have upgraded to 7.5 yet. [MHA]
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.