Paul T Barton Says:
For now and since about 2010, I have been building LED cubes using PIC 18F4321 chips (TQFP and DIP-40). I have a pile of sub-routines related to the editing portion of these cubes. I tie the serial port to USB through a teensy USB PCB. Editing is the heavier portion of these cubes as I tend to believe in creaping-featureitis. If any of you would like to see some of those routines, holler back. For now I only use mono LEDs or two-color (Red/Green) LEDs.
Paul T Barton Says:
As to the hardware, I am using CAT4016 cathode-sink shift-registers (16 bit wide) and P-channel FETs (IRF7306) for layer/anode drivers. This means that most of the LEDs are common cathode ones (so far). Biggest so far is 8x8x8 green and smallest is 2x2x2 yellow while I have one made up of SMD-1206 LEDs. I have a couple of u-tube clips under the name "IdeZilla".