One usually doesn’t think of standard tools in the shop as high on the list of “techy gadgets” but one tool is using a pretty neat technology to help improve safety.
SawStop has table saws on the market that if any part of the user’s body comes in contact with the blade, the saw instantly stops, and the blade retracts into the body of the saw.
How does it work? There is a small electrical current that runs through the blade. Inside there is an electical sensor that if it senses a change in the voltage (by a finger, or in the case of their demo, a hot dog), it triggers the brake which stops the blade. The momentum of the spinning blade stopping in a fraction of a section pulls it down into the body of the saw. Pretty cool stuff. Check out the vids below.
Of course, they are not cheap. I think last I saw about $1800 for the contractor model, and $3800 for the cabinet model to start.