On Tuesday Microsoft unveiled Live Mesh. Microsoft already makes a technology preview of Live Mesh available for you to try.

Microsoft Live Mesh uses the Internet as a data hub and synchronizes files across computers, phones and other devices. Additionally you can share with others and stay up to date and access files from anywhere. Live Mesh looks actually pretty neat, but maybe also just another way for Microsoft to trick you into a Passport account.
You can try Live Mesh on the mesh.com.

To learn platform and services approach and the thinking behind Live Mesh you can read this article by Amit Mital, Microsoft General Manager and see this video interview with Ray Ozzie on Microsoft's Channel 9.