A ssh tunnel for Firefox to a remote computer is good security measure. Especially when connecting via an untrusted network like a wifi hotspot or other public networks. The tunnel encrypts and sends the data to your remote machine then it is sent over the web to your destination. This tutorial assumes you have an account on a remote machine you can ssh into. This is a pretty easy set up.
If you want to try to scare novice attackers, it can be funny to display a banner containing legalese. This doesn't add any security, because anyone that's managed to break in won't care about a "no trespassing" sign--but it might give a bad guy a chuckle.