Hi Ben,
As the world around us gets smarter and smarter it would be nice to build some device(s) that would make all of our lives also a bit smarter. Think of a DIY sensorboard, curtain automator or relay board that communicates with a single base station and is easy to use. How cool would it be to set up some sort of basic home-API and control your home from pc, phone or physical switch. It would even be possible to make some schemes for when it gets dark or when it rains!
Hope you're able to do a project like this on your show!
Greetings,
Ton Smets
(A very enthousiastic viewer from the Netherlands)