I often have to work behind "smoothwall". AFAIK, it only allows HTTP over port 80 and HTTPS on port 443 - any other protocol on any other port gets blocked, including other protocols over port 80/443.

To bypass this, I wrote a simple ruby script to tunnel TCP connections, while adding fake HTTP headers to get through the firewall.

Actually, yes, packet inspecting firewalls do. Hence the SSH over TLS, to make things stealthy.