Ive been wanting to add a stop paddle to my table saw for months now and the other night, I was looking at another ww forum and there was a thread asking for design ideas for a stop paddle. I copied one of the designs, and here is my paddle. I have a Unifence, there is a 1/4" t-slot on the bottom side of the rail. Thats where I attached the paddle. Its made from 1/2" plywood and a 3" hinge. It works great and I should have done this when I fist got the saw. It looks like its sitting on the floor, but is actually about 3/4" above. I had to add the piece at the bottom because I didnt have a large enough chunk of plywood. It sure makes things safer because I dont have to take my hands off of the wood and search for the switch. I was surprised how little pressure from your foot will activate the stop switch.
Maybe this post will stimulate some of you to make this simple and cheap mod to you table saw.