SSH Port Forward

Allow port forwarding on the server
# Edit the /etc/ssh/sshd_config
AllowTcpForwarding yes

Local Forward
# create a tunnel to access an ssh server behind a firewall using a gateway
ssh -L 7777:192.168.1.160:22 gateway.example.com cat -

# access the ssh server via your local machine
ssh -p 7777 localhost

http://www.securityfocus.com/infocus/1816