Simple,Secure File Sharing, Syncing, and VNC Offered by Gbridge

Free application Gbridge creates a virtual private network between any computer over the internet based on your Google account. The app lets users share files, connect to and remotely control a computer using VNC, sync folders, and back up files to another computer.

In case you have Google Talk/Gmail chat friends using Gbridge, the program makes possible identical functionality between your machine and theirs. As simple as it may sound so it actually is. You can easily create a VPN between computers, and supposing you do have a Google account, you don’t have to make any further signing up. However, there is some room for improvement for the app with respect to its intuitiveness in practice, and to be more precise, in what it accomplishes. Contrary to what some might believe (because of the name) there’s no connection between Gbridge and Google.

The application is freeware and supports Windows only. From the site about the VPN infrastructure:

Gbridge Revolutionary VPN Infrastructure
Gbridge automatically forms a VPN among your multiple PCs no matter where they are. You can also extend the VPN to include your Gtalk friend's PCs if both sides allow.

Great extension of Google's Gtalk infrastructure, self-forming, zero-config.
IPv4 level compatibility while providing authentication, encryption and mobility.
P2P direct network connection, excellent privacy and great performance.
Dynamic DNS and private IP, solve the real world naming and connectivity issues for almost all network applications.