Okay, just to keep you guys up on what were we doing, here's a picture that can save me a bunch of words:
Here's our toy: An arduino (thus far on a breadboard), some serial-to-parallel ICs (can't remember their numbers as for now... I'm posting from home!) to issue row/column addresses with not-so-many pins and the 8x8 button/led array, which we will use while in prototype stage, the final piece shall be a 10x10 array. As for me I think that humans should cut one finger off of each hand so that we could be compatible with computers, but most people don't like this idea for now, I bet that people in 2099 will call me ahead of my time!
Now we're handling software, which will be the biggest part on our project, we aim to be arduino-compatible but these arduino tools are pretty slow, I hope in the end we can achieve that by using an avr-gcc-based lib to arduino in such way that all the logic will be handled by arduino and all the operation in gcc's form factor. Worst case scenario, we will have everything in C, but we are working to make this project not only buildable for everyone, but also workable/hackable.
PS: if you look close, you'll see that many pins were left unconnected, at that time the unit was partially disassembled!