I'd like to put some kind of large, nice-looking, interactive exhibit on the wall in the hallway by our museum. Perhaps something that shows how data is created, processed, and outputted in an electronic digital computer, regardless of whether it's a modern system or an old one. Something where kids can press a button, watch the circuit make a decision, and follow along as the lights change leading to some result. Looking for serious/constructive feedback from people who are willing to actually do work. That should narrow the replies. :)