JavaScript effect that will let you edit any webpage

This is a pseudo-hack.. you're not really changing anything on their server, but it lets you play around with websites layout and objects that are usually locked. You can edit text, move pictures, etc.
Only works in Internet Explorer as far as I can tell, since Firefox disables javascript by default for security reasons.

1) Go to any website

2) Delete everything in the address bar

3) Paste the following code in the address bar:

Code:

javascript:document.body.contentEditable='true'; document.designMode='on'; void 0


4) Start playing