Email to Seb

I emailed Seb to tell him what I was up to and to ask about 'catching' touches on arbitrary surfaces. His reply was informative!

Usually in these kind of installations, you'll have a screen that's projected on and infra red lights to pick up touches on the screen. But that kinda depends on the screen being semi-translucent. I don't know how easy it'd be with solid bricks!

It might be that you could add sensors to each brick, but at that point it becomes a fairly major electronics project!

From this, I understood that it wasn't impossible, which was what I was after with hints towards how it can be done. I now have the means to start some research into the idea - more posts on that to follow!