They list a few here:
http://www.panic.com...rst-emoji-domain/

I tried posting the URL here. It looked OK when I pasted it in the edit box, but it was converted to this when I previewed and it no longer works as a URL:
http://💩.la/

The poop one looks like this when viewed in Safari. Doesn't show up in Firefox or Chrome though.
http://www.ideograph...images/poopla.png

Image from here:
http://www.ideograph...rticle.php?aid=81