Statics on a desktop computer?

I do not know how to describe it correctly, I will try as it is. The computer is connected to a power outlet (with ground) through a surge protector (also with ground), speakers and a monitor are also connected to the surge protector. The upper part of the body is metal. If you turn on the surge protector and move your finger along the upper metal part, you feel a small discharge, in childhood many probably tried the crown on the tongue, that's something similar.

So to the question, is it possible to somehow eliminate this, is it harmful to the computer, can it shy away from the upper metal part more than simply by static, and does this mean that the socket is without ground?