iTornado is actually an update of a PC-to-PC transfer product that came out last year under the brand Data Drive Thru, but with the rate of Windows-to-Mac switchers, there's now an omnidirectional version that works with any combination of PCs and Macs. The software for both platforms is embedded inside the retractable USB cord housing. iTornado will be available in March for $80.
Included is a piece of software called PC Eraser, which deletes all your personal data from the PC you're transfering from but leaves the OS intact. This makes it easy to then donate your old PC to a school or whatever.