Over at the Maker Faire there was a life-sized Mousetrap.  Although the ball needed some coaxing down the flight of stairs the first first time I watched, it still managed to work better than its gameboard version from when we were younger.  The second demonstration that I saw flowed flawlessly.

I didn't have a good view so I didn't take a video, but here is a video I found on Youtube taken at the Faire.  This is one of the times where the bowling ball needed some help down the stairs.

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MAKE: Blog: Maker Faire: The Life-Sized Mousetrap