I have a set of something similar, but they're played with mallets and the tongues are more flush with the body. They call them 'Tank Drums"; and they're essentially a tongue drum made from the bottom of a propane tank. We used them in the pit at Cavaliers last year a few times.
Jim- I saw those in Erik's office back in August. Those things are pretty cool! Alot more resonant sound than I expected. Seems like an easy enough project to mess around with... Might be a X-mas break experiment!
BTW- Excited to see everyone at PASIC! If anyone is available, Friday morning I will be performing a concerto with the UNT Percussion Ensemble at 10:00 am. I hope to see some of you there! :)