I've done some work getting older (FTDI based) arduinos to communicate with Artemis. They use the same FTDI chip that the Entec device uses, as such an Arduino Deicemilia (http://arduino.cc/en/Main/ArduinoBoardDiecimila
) will start receiving data from artemis when it starts
So far I've hooked an LED to the Shield status and had the arduino keep track of "player got hit" messages with a view to triggering a smokemachine that I have.
Anyone interested in the code? Its in the development forum at the moment :)