LED cube

largely out of boredom I recently noticed I had a couple of spare micro-controllers and a few bags of leds lying around and decided to take a crack at making an led cube.
Led cubes are low resolution 3d displays.
Looking at what had gone before I noticed that may people were using attiny2313's like my spare micros to drive these systems but all were "small" 3x3x3 models and were using all the available io, I decided this was insufficient and pushed for 4x4x4 and after a few hours of thought and planning knowing 64 leds from 16 io pins had to be possible I set to with the soldering iron and produced a messy but functional cube.
The programming has taken longer than it should have, I hadn't realised how rusty I'd allowed my c skills to get, or really looked properly through the avr libraries. but now I have my new led cube which unfortunately has reached the point where it works and is easily programmed to display different things and hence my interest has faded as the challenge has gone.
I'm attaching my source for any one interested pointers and opinions are always welcome.
The cube itself is built in eight, eight led blocks which share a common cathode and individual anodes, each block shares all its anodes with all other blocks. The blocks are arranged in 4x2 units on each layer (two blocks to a layer). By holding all cathodes high apart from the one I currently wish to illuminate any single led can be lit on a layer, by quickly cycling through the cathodes it is possible to produce “static images” on the display.

By changing the image displayed it is possible to produce animations, within my code there is the notion of frames, these are a static image for display, and a sequence this displays multiple frames in sequence to produce animations.

I'll upload a few pictures when I can remember where I put my camera, and maybe some video of the animations.

p.s to build the code (if any one feels the urge for whatever reason) one will need winavr utilities