When my wife uses her laptop, if I touch her skin, I can feel a buzz. She doesn't feel the buzz, but she can hear it if I touch her ear.
So I'm guessing it's a faulty laptop, and she's conducting an electrical current.
But why would she not feel anything, and what would it be that she would be hearing when I touch her ear?
The effect is only intermitent - it's pretty reliable in a single session on the laptop, but some sessions it won't happen and others it will.
I had the same sensation with a desk lamp that I had several years ago, with no moving parts (as far as I could tell)
The effect only occurs when I move my finger - if I'm stationary, I don't notice anything.
I was playing with my son, and noticed the same buzz. First I thought he was touching the laptop. Then I realised he had skin-to-skin contact with my wife who was using the laptop.