The Global Spec Brain Strainer

Every engineer needs small diversions and puzzles to keep their brain sharp during the rigors of a tough design.  Here's one that I discovered today at Global Spec (the engineer search engine): The Brain Strainer.

My latest rocket launching machine can be viewed at this link.  It works best with the wooden ball, but also works with the rubber ball.  It isn't the highest scoring machine, but it is much more interesting in that the ball jumps around the whole board quite a bit unlike some of the highest scoring machines.  It doesn't work with the metal ball.  Please post links to your own machine designs as a comment to this entry!