By accident I just discovered the new 3D Page Inspector in Firefox 11. This is a cool feature for web developers and -designers. A very awesome and intuitive way to analyse websites.
Here are two videos, the first one shows what it does and also shows another nice feature. The second one shows how you can „abuse“ this new page inspector. And I’m really looking forward to people doing this!
If you already got Firefox 11 and a computer that supports the feature, you can check out that demo yourself.