And now for something completely different... An Arduino Duo with a Adafruit Audio WAV shield stacked on top along with a SD card reader. On the breadboard is a status LED and a Parallax passive infrared sensor. The Audio shield came in kit form so I just had to do a bunch of soldering to get it ready. Biggest challenge for that was keeping the kids away from the hot soldering iron. Fortunately it worked the first time. The software to manage the infrared sensor is trivial. The software to integrate the Audio shield into my project won't be nearly so easy.
I have several applications in mind for this prototype development but they're all top secret :). I will keep my blog updated.