NYT has a review of Seagate Free Agent, the new portable hard drive from Seagate. The external hard disk works with both Mac and Windows. Excerpt:
"Seagate’s FreeAgent Go hard drive is the first portable, self-powered drive to feature a docking station. Connect the 6.35-ounce dock to your PC and you can sync up like any iPod.
The Windows version is compatible with Windows Vista and XP. It also has software for automated backups, encryption and password protection. So even if you lose your data, it will be hard for anyone else to find it." Link.