Firefox and the acronym tag

I just stumbled on something cool with Firefox. Try using the acronym tag, thus:

<acronym title="Spell Out The Acronym Here">SOTAH</acronym>

And the associated stylesheet:

acronym {
  border-bottom: 1px dotted #222;
  cursor: help;
}

The result is YATLA. I especially like the mouse pointer change (at least on Windows).

Thanks to this page on ISBN bookmarklets.