Its more like static charge comin out of the laptop keyboard. I would suggest while the laptop is off, clean it with anti static spray/cloth and then try it.
If problem still presist then I am not sure what else can be done, as you mentioned that electric flow in your house is fine, I don't see any other point for the little shocks.
Have you tried it somewhere else within a house or at friends house? Try it and see, perhaps it might be that point where it is plugged in or perhaps its in the house? I'd test it at someone's house to be 100% sure that it is not the house electric but the laptop itself.
I all doesn't work then might as well get a new laptop
Sorry couldn't help much here as I never heard of this kind of problem before.