AHP -
Please consider documenting these kinds of formats. As a commercial software vendor I realize that opening up can cause you a lot of support grief, and limits your flexibility to make changes later. However, with such a 'hackable' (I mean that in the original sense) product, allowing others to assist in extending the capabilities of the unit can only be good for it. This thing could be another Palm Pilot-like success story.

Along the same lines, it would be great if you could publish the specs for the serial communication port -- I don't mean the cable pinouts, but the protocol. That way you'd have people writing Pronto control software and libraries for Mac, UNIX, etc, without you taking heat for not writing software for them.