General Information
You are somewhere that has a restrictive firewall/web proxy, but allows SSH. This trick allows you to tunnel your web browser's traffic through SSH to a remote system and browse the web as if you were at that remote system.
Checklist
1) Open a SSH tunnel to the remote system and specify a dynamic application listening port (Example: -D 1337):
ssh -D 1337 user@yourhome.com
2) Edit your browser proxy settings to use the same port SSH is listening on.
Firefox Quantom