This Honda commercial from a few years ago is a beautiful example of how you can use Rube Goldberg-type effects in visual communication.
How to use it in PowerPoint? Animating one of these machines is a challenge... Two suggestions.
- Build up audience anticipation. Use a simple cartoon to create a tension about something that is about to happen. The same way that a novelist leaves room for the reader to fill in the blank spaces. See an example on Nancy Duarte's blog: the hanging piano that is about to fall is a more powerful visual than that of a broken piano on the floor.
- "There must be a better way to do this". This is a concept I often need to get across in fund raising presentations for technology startups. Showing a very complex Rube Goldberg machine does the trick for me. (Another technique making the same point is using vintage images, here an "auto wash bowl" long before the automated car wash was invented).