How about a captive nut.

Has mystery and not too many steps.
Somebody gets to go home with a cool toy.

http://www.youtube.com/watch?v=fdh7-86kE4I


"Pete S" wrote in
:

----But, we are in the process of setting up Machine Shop sections
within two of the venues that I attend annually. So we are in need of
projects for this part of the shops that will "wow" them and at the
same time teach a little.
What do you folks do?

Pete Stanaitis
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