I have one more Firefox 3.6 about:config tip up my sleeve.  By toggling one setting, you can go from having a drop down list of tabs to a thumb-nailed view of each tab that is open. 
Here is how you too can enable this secret Firefox 3.6 feature.

Here are all of the useful (and not so useful, but still funny) about: triggers you can type into your address bar.
about: — The same page as “Help -> About”.
about:blank — A blank page. Useful for setting as your homepage.
about:cache — Displays cache statistics and disk cache directory location.

about:config — GUI for modifying user preferences.
about:crashes — List of Breakpad crash reports, with links and datestamps. Only in products based on Gecko 1.9 or later (Firefox 3, Thunderbird 3, SeaMonkey 2).

about:credits [...]

For those of you playing with Firefox 3 – Beta 5, try typing about:robots into your address bar and hit enter.

So what does Klaatu Barada Nikto mean? Shame on you – this is one any geek should know…

Want Firefox to help you encrypt your secret files and documents? Maybe you just want to learn more about the encryption process? No matter which camp you fall into, the Fire Encrypter Firefox extension is for you. It brings the top secret world of encryption right into your favorite little browser.
[Learn More About Fire Encrypter!]

Easter eggs hidden away inside of programs is nothing new. What I didn’t know till this morning was that even Firefox has a few tricks up it’s sleeves.
It was a lot of fun to read but one thing that really struck me as interesting was this about:mozilla “Easter Egg” that they mention. The Book of Mozilla has been something that even the first version of Netscape has had in it. You can pull it up in Firefox/Netscape [...]