Changing favicon dynamically (icon change only works in FF/Opera). This demo only tested in Firefox

FAQ below. To see the favicon change in a background tab, try the animation demo.
1. Type a letter.
Hold shift key to change title
Hold ctrl key to scroll title. Ctrl-0 to stop scrolling.
2. Look up. Favicon has changed.

- OR -

1. Type [

2. Look up. Favicon is animated. Type ] to stop animation.

Icon Credits: Ed Babinski