Acer Aspire 5820T lid has a slight shocking feeling when plugged in.

Hello,

My Acer has a slight shocking feeling(Maybe those who used the Asus Transformer Prime may know this feeling) when you run your fingers along the lid while it is plugged in. Im curious as to why this happens, if it can harm the laptop and what, if anything, can be done to remedy it. Also, the laptop is out of warranty, in case anyone wonders.