LogMeIn Hamachi is a hosted VPN service that securely connects devices and networks, extending LAN-like network connectivity to mobile users, distributed teams and business applications. You can easily create secure virtual networks on-demand, across public and private networks. Hamachi is managed and maintained from anywhere via the web, securely.

Features:
Web-based management, remote deployment and easy administration
Instant and managed networks, with gateway and hub-and-spoke options
Embedded network security with encryption, access controls and config management
Commercial use with up to 256 clients per network; free for non-commercial use