You can certainly build a computer out of legos. Or at least a Difference Engine, and what really is a better introduction to computability than making your own

You can certainly build a computer out of legos. Or at least a Difference Engine, and what really is a better introduction to computability than making your own calculator? http://acarol.woz.org/difference_engine.html http://acarol.woz.org/difference_engine.html