GRE Tunnels and Encryption
GRE tunnels rock. They are interfaces on a router that are used to “connect” to another router somewhere on your LAN, your WAN, the Internet, wherever. The most popular use for them is for router-to-router VPNs.
I’ll let my friend Josh from blindhog.net show you how to do it. He’s got a video on how to configure the tunnels, and another on how to set it up for VPN.