Ben,
I enjoyed your shows. I like the premise of many sinple and faily cheap builds grouped around a large and intricate build.
So, here is my idea for a simple, cheap, and yet stimulating build. How about building a smart socket. I'm refering to a 110v/220v wall socket. The socket should be able to determine the amount of current being drawn throught it. It could also have the ability of being remotely controlled.
Yes, there are similar propducts on the market that do either one part or another but not everything. A "kill-a-watt", for exanple can only monitor a single outlet. While a "TED" only monitors the total current at the mains. If this can be built into a single unit that replaces all sockets and then networked together you could easily monitor and contorl an entire building.
There are 3 main parts, the socket, the mains monitor, and the interpreter software. I beleive if you are able to complete the first then the rest of the audience will be motiveated to complete the other parts.
How would your audience benefit from this project?
First, you can introduce them to current transducer. Not being an engineer or electrician this is my biggest hangup.
Secord, "help save the planet". If this is something you or they care about then being able to monitor their uses woudl be beneficial.
Third, its cheap. A 2 outlet socket is around $5. I picked up 3 CTs for $20. At this point I am using an arduino($30) for testing. When depolying on a large scale you may be able to recommend something cheaper that will still allow network communication.