Microsoft Live Mesh

This is the software publisher's description:

If you need to access the same files from different devices, Live Mesh can help.

With Live Mesh, you can synchronise files with all of your devices, so you always have the latest versions handy. Access your files from any device or from the web, easily share them with others and get notified whenever someone changes a file.

Working on one computer, but need a program from another? No problem. Use Live Mesh to connect to your other computer and access its desktop as if you were sitting right in front of it.