Yet another crazy cube idea. one of the nice things about this setup is that you dont use too much current, and you dont have to worry about mosfets, It does require more parts than the charliecube, but its only 16 transistors. Because it only lights up 12 LEDs at a time it only uses 240 mA, but it has a duty cycle of 4%, so it wont be very bright.
Here my modification of a 5x5x5 transistor cube (thanks crossroads), that I changed to 4x4x4 RGB. I didnt quite draw all the lines in, but hopefully enough is there to get the right idea.
At this rate, I may never get the original cube SMT constant current cube finished, or the shift register-resistor cube built.