The guys from Buglabs posted an article where they explain how to connect their box to Arduino. On the picture you can see an Arduino Mini, a USB-Serial converter and one of the Buglab´s devices talking over a USB port.

picture (c) 2008 by Jan Rellermeyer at Bugblogger.com

It would be fun to try this out by ourselves … if you guys wanna send us out one of your machines, we can publish some nice articles about how to make those two kids talk to each other ;-)