My home computer is behind a firewall that I do not control and blocks all (yes, all) inbound traffic. Nearly any outbound traffic (and replies associated with it) are allowed, though. I would like to have SSH access to my machine. Given a friendly server on the Internet, I could use SSH itself to forward a port on the remote server to port 22 on the home computer, essentially using the remote computer as a secure proxy.
I do not have such a friendly server. Does there exist a service that offers to port forward in this manner?