On Sat, 28 Jan 2012 23:07:49 -0500, Bill wrote:
Nice idea, it could detect if a finger were on the table near the blade.
Unfortunately, most accidents seem to happen in direct contact with the
blade--in midair. Using an electrical circuit to detect contact seems
to be practically unavoidable

That's why I suggested some type of beam of light being broken as a
stop mechanism. Sort of like the mechanism of an automatic door
opener. It detects movement and operates. All that would remain is for
it to distinguish between flesh and ignore wood/everything else.