If you regularly visit our FTP site at <ftp.tidbits.com> for Macintosh Internet software, be aware that we're moving files and directories around. Things may be rather difficult to find for the next week or so. I'll write more about the reorganization once it's complete. [ACE]
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-]).