I have no idea how feasible this is, especially in the span of a week, but maybe it's cool enough to do as a side project across multiple episodes.
The idea is to make a pinball playfield that can change shape as the game progresses, inspired by the MIT inFORM system (http://tangible.media.mit.edu/project/inform/). Think of it as a dynamic version of your own pinball rapid prototyping system!