I had a Boston Terrier that was deaf. I didn't know it at first since she was so alert, but from behind or when she was asleep, she didn't hear a thing.
We looked online for information on deaf dogs and found all sorts of websites with the signals your looking for. She undersatands about two dozen signs.
Funny thing is, when she's been bad, she wont look at you, or will turn away in order to avoid the bad dog sign. [img]/forums/images/icons/wink.gif[/img]
Just seeing that sign will make her squinch up and cower, but the good do sign will make her all happy and exited.
It always amazed me how she read hand signs and reacted to them.