Hrmmm, lit ones hey:

G5 Power Light
Monitor Power Lights (2)
Optical Mouse LED
PowerBook Battery LEDs (4)
Stereo Power Light
Stereo Display Backlight
Messages on phone (flashing)
Switch Power Light
Switch Link Lights (4)
Battery Charger (2)
Digital Clock Segments (18)
Total: 36

Maybe some more if I kept looking for electronic devices hiding under things

- proton