I'm gradually digging into the backlog of new software that Apple has been shoving across the Internet onto my hard drive, and finally got around to configuring iSync, a feature of the .Mac service. I never thought something so simple could be such a big deal–that is, until I suddenly found all the addresses and calendar entries on my laptop, desktop and Handspring synchronized.
Now, mind you, the results require a bit of a merge-purge, since I've had seperate versions of all this data in my e-mail, on the Handspring, and so on. But by pushing the button on the Handspring's cradle, I now sync the desktop and the handheld with the data from my laptop.
The Handspring's synchronization was somewhat temperamental (it crapped out on address book synchronizaton the first time through), but that's been my experience with the Handspring in general with OS X).