Here’s an experiment my brother and I did a while back, involving high voltage and pickles.
The setup is an electrical cord stripped, and wrapped around two nails. The nails are the terminals that transfer the electricity into the pickle(s).
For safety the modified cord is taped down to the work surface and plugged into a power strip with a isolated switch and fuse. This allows some safety (the 15A fuse) and control (the switch) that we used to start and stop the experiment.
Immediately after switching the power on, the pickle lights up with a flickering pattern. One side of the pickle generally lights up more then the other. There was some smoke that was hard to photograph, and the smell of burning pickle.
The flashes seem to be the spark the terminals make when an electrical connection is made, The translucent nature of the pickle's body lets you see the spark pretty well.
My theory is that the high sodium (salt) water content of the pickle makes the pickle a relatively good vegetable to transfer electricity though.
Generally the smaller the pickle, the better it lights up. I assume that was because there was less pickle for the electricity to travel though.
After a minute or two the terminals burn though the pickle and the char would make the connection from the terminal to the pickle less effective.
Above you can see the different sizes of pickles we tried.
All in all, it was pretty interesting, and good times were had by all.
Warning: there are potentially lethal levels of electricity involved with this experiment. If you are not familiar with the safety practices you should use with electricity, do not not attempt. Seriously.