When I have my powerbook plugged into the power supply if I shut the lid and run my hand across the back of it I can feel what feels like electric current running through it. I have read one other thread on this where the guys powerbook actually shocked him, which thankfully has never happened to me. I just want to know if this is something I should approach apple about to get fixed or is it just a 'normal' thing that everyone gets that is inherent to the powerbook design?