C-Command Software's powerful Bayesian email filtering tool SpamSieve has been bumped to version 2.8.3. The update adjusts SpamSieve's tokenizer to make the spam filter even more accurate. In addition, SpamSieve now supports pre-release versions of Apple Mail, MailForge, and the upcoming Microsoft Outlook 2011. A few issues with installing the SpamSieve Apple Mail plug-in have been corrected, too. Full release notes are available. ($30 new, free update, 7.1 MB)
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-]).