Don't stick your finger in the electrical socket!

When we took over the lease at our place, we inherited a bunch of extraneous stuff. For example, in our kitchen we have both an overhead florescent light, as well as some crappy track lighting. (See image)

I have tried to keep the track lighting unplugged, on the advice of an electrician who told me it's illegal as well as dangerous. However, Mark keeps plugging it in every morning before he goes to work.

As I reiterate to Mark that I don't want the track lighting plugged in, I notice him sticking his finger into the electrical socket in question.

Me: "Mark! Stop that! What the hell are you doing?"

Mark: "I'm just wiping dust out of it."