Azrael wrote:

>The real project is designing "smart" building-blocks.
Azrael, I don't know if it will help with your project (which is GREAT by
the way), but just in case, you should look at

http://fredm.www.media.mit.edu/people/fredm/projects/ab/

This is a sketch of a project that "instruments" lego blocks, such that a
computer could track a construction. There are good ideas here, using a
simple resistor to identify blocks, etc.

If nothing else, I'm sure it will be an interesting read for you :-)

Dave Johnson