The current MP3 player, now based on the ATMAL AVR microcontroller.  (Here is the old one)
I dunno, just a pic
The whole thing
Power supply. And yes, just one 1.5V battery
Close up of power plant. 3.3V on the left, 5V on the right.
CPU and MMC card
CPU, decoder, and DAC
Front view
Decoder card
Decoder Support parts
CPU again, real close
MMC card and socket
One last shot of the power plant.