And now, for something completely dorky. I have begun to play with DIY electronics. This is principally because it's tremendous fun. You should try it. Seriously. The possibilities are endless. Here is a video of a range test for my prototype homing device built with an Arduino microcontroller module and an XBee radio transceiver. The portable, handheld device cost me about $60 to make, but theoretically could be a lot less if you designed a PCB and didn't rely on prototyping components.

Short-term, I hope to join fellow Boston Dorkbot members to build on this prototype and construct a location-based game. Stay tuned... My longer-term goal is to develop a standardized radio/microntroller platform on which to load and share user-oriented software applications (like the homing software shown here) for proximity-based device communications. The range for the "homing device" seems to well exceed the 300' that the XBee specs claim. Cool. Please send me suggestions for improvements, other ideas, etc.