Back a number of years ago we had a young lad come to the shop to work part time while attending tech school. The previous night at school the lesson had pointed out that wire, (while considered a conductor) did have some resistance.

On the shop floor was a 5000 foot spool of small gage wire. In order to reinforce the previous nights lesson he decided to measure the resistance of the spool of wire. He put his meter on the resistance scale and made a measurement. When he removed the meter leads he drew a half inch arc that gave him a good jolt.

We explained to him what had happened by describing the operation of a car engine's ignition coil. But it didn't help much. After that he was reluctant to make any kind of measurement using a volt/ohm meter.