Okay, bumping this thread to the top as I've done more research.

I'm leaning more strongly toward an OS X PowerMac, so I've been doing more research on the various sticking points. A lot of my pain comes down to my cursed Ericsson T39 phone. If I'd gotten one of those PalmPilot phones, this wouldn't be a problem. But it is.

My cel phone speaks SyncML, for which the only synchronization solution today works with Outlook on Windows. (There are numerous SyncML libraries out there, including one in Java, but nothing that's integrated into PIM software.) Now, there are two ways to talk to the phone: serial or Bluetooth. To do either on the PowerMac, you have to have a USB adapter. So, then the issue is how to rig this all the way through to VirtualPC. According to the vendor's web site, you can choose USB devices to "unplug" from the Mac and then plug into the VirtualPC.

The current question: USB serial or USB Bluetooth? I'd prefer Bluetooth for its speed, but good luck finding a Bluetooth device with drivers for both Windows and OS X. The nifty D-Link gizmo that Apple is promoting has no Windows drivers. Okay, so that means I have to go serial, right? There are a bunch of USB serial port adapters although the coolest one seems to be this one from USBgear, which also has PS/2 ports so I can use my Kinesis keyboard.

The other thought I've been pondering is perhaps getting (yet another) new cel phone. The required features for me are global GSM, some kind of PIM functionality with synchronization, and light weight. The reason I didn't get the Kyocera or Handspring phones in the first place is that they're monsters. The T39 is only 86 grams. A Handspring Trio is nearly twice that: 147 grams.