http://cgi.ebay.com/ws/eBayISAPI.dll...3759 354&rd=1
That's the only battery operated one I can find
http://cgi.ebay.com/ws/eBayISAPI.dll...4937 595&rd=1
That would be nice if you didn't need batteries
Although I'm sure there's probably a cheaper/more ghetto way of doing all of this too.