Re: Stuck a finger...
Back when a student earning a few pounds in a TV shop doing deliveries and repairs, we regularly worked on TVs when live. A screwdriver held about 1/2” from the cap of the line output valve would draw an arc - if it didn’t you knew the fault was in that section (usually the valve or the LOPT). Was seconded to a workshop in a neighbouring town and tried the same trick on a TV with a suspect line output fault. Unfortunately they ran their workshop off an isolating transformer and ELCB - killed all power on the premises. Easily sorted…
On another occasion (when still a student) I was sent to an office to check why a microfiche reader wasn’t working. First check is for mains power so eased the plug partially out of its socket and put a “mains test” screwdriver on the live pin. A loud bang and whole ring main on that floor went down. I hadn’t noticed, in the dark corner, that the socket had one of those fancy brushed steel covers!
A third tale, from when I was a toddler. My gran’s house had pre-13A wiring and one of the sockets on the wall beside the tea-table was a co-axial mains affair (never seen one anywhere else and nobody knew what it was for). I poked my finger in (as one does as a toddler): luckily, my finger just shorted live and neutral so the current had a short path across the tip of my finger and no current went through me. A jolt and slight burn.