A quick hack on an ssh reverse tunnel (i.e. from behind a firewall)

This partially from an article on techrepublic:

http://articles.techrepublic.com.com/5100-10879-5779944.html?tag=nl.e011
On the host behind the firewall you want to pierce, run:
ssh -nNT -R 2222:localhost:22 user@routablehost