RAM Doubler, PowerBooks, and 7.5.3? Connectix reports it's investigating a problem using RAM Doubler 1.6.1 on PowerBooks. Apparently, the machines may crash when they wake up if they're running System 7.5.3. According to reports, installing Apple's low-level debugger MacsBug prevents the problem from occurring. [GD]
Go Back and Forth Fast in Preview
If you're reading a PDF in Apple's Preview software, and you follow a bookmark or an internal link to move around within the PDF, you can quickly return to where you were by pressing the keyboard shortcut Command-[ (that's Command-Left Bracket). Or, you can choose Go > Back.
The command works iteratively, so you can go back to just the previously viewed page or if you issue the command again, to the page before that, and so on. There's also an equivalent Go > Forward (Command-]).