AC Adapters for PowerBook Duos may all look alike, but they're not all the same. Apple just introduced a new unit, with item number M4174LL/B, which works with the new Duo 280 and 280c models, as well as all previous models; it replaces M2781LL/A, introduced earlier this month, which also works with the new and old models. The M4174LL/A adapter works only with the Duo 210, 230, 250, and 270c models. The new item number for the adapter that works with all Duos was probably adopted in order to avoid confusion. Nice try. [MHA]
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-]).