After looking through a few of Chris O'Shea's work I realised how a lot of his work responds and reacts according to user input. Like it will follow the user as they walk past.
So for my project I could mention how the user doesn't have much of an impact on the shadows from natural light, but it seems that although the shadows obviously change position very, very slowly, the audience very rarely notices this. So the 'piece' moves, but the user doesn't notice. A lot like the moving box thing that the iDAT guys did a year ago (don't think it works anymore).
So yeah, that could be something.