The other day I broke a socket while changing a spark plug! At first I panicked. How do I get the broken piece(s) out from way down in there? First I checked the remaining part to see if it was magnetic, it was. Then none of my magnets would fit down in the opening. So I used a magnet and ran it across the end of a flat blade screwdriver. That did not work. Then I took a stack of magnets and ran that across the end of the screwdriver. That gave the screwdriver just enough power to just so lift the part up to where I could get a hold of it. Whew!
After breathing a sigh of relief I then changed all of the other spark plugs with a different socket.