You could also use a cheap circuit tester (cheaper than a multimeter, but does the same thing in this case). I would be inclined to test for a current to the grounded part of an outlet....actually, for you brits, things may be a bit different.

I seem to remember that there was an actual wire on early PC's that grounded the case explicitly, simply because it was part of the ground for the system. I haven't seen such a thing lately. Your problem could be simply that the ground is not working right and your case is acting as a capacitor.

And that's about as much as I know about electricity. However, it is more than dglienna who is testing for live 110 wires with body parts

(my hand sure isn't what I'd use first, back OR front)







(I'd use my tongue)