also the point isnt to ground yourself, which many of you are over looking, the point of it is to discharge static electricity which can easaly be done by contacting any sort of metal. hense touching the case. there is less of a danger to your more so a danger to your pc parts.
The worst thing about ESD is that it doesn't show up right after it happens; so you could go for months thinking your computer is fine and the suddenly it doesn't work.