This morning, I stumbled on this article: Firefox inside Firefox. That article brought up a really cool Firefox trick which you can open a Firefox browser in a Firefox browser. Technically speaking, it's a nested Firefox, or in short: Nested Fox.

And to my surprise, it's easy to do the trick, you only need to type and run this url: chrome://browser/content/browser.xul.

There are some limitations on how many Nested Foxes that you can make:

1. You feel extremely bored
2. You can't type on the last Nested Fox url bar
3. Your Firefox crash
4. Your Mac has run out of battery
5. You are drunk and got someone waiting on the bed

But apparently, Firefox 3 has successfully eliminated the 3rd limitation.

And my last word, I know I can't stop you from trying this out on another browsers, but please don't sue UsingMac.com if anything happen to your Mac (or PC)..