Has anyone else had this problem? When I have my Powerbook G4 17" 1.0 plugged in using the power adapter, I get a strange 'vibration' feeling when my hand runs across the top of the base just below the keys and around the track pad. When I am typing, I often get little electric shocks on my wrists where they are touching the forward edge of the keyboard. It kind of feels like a hair is getting pulled out of my forearm, but it is a little electric shock. When the mac is on my lap, I can touch another person and feel the 'vibration' feeling through my finger so I assume it is an earthing issue? As soon as I pull out the cord and go to battery power it stops. Does anyone know what this might be and is it dangerous at all?