To add to Manhattan's post:
Adding a single wire to a metal water pipe is more dangerous than no ground at all in 99% of the cases.
It is allowed in rare and specific circumstances. But even under those circumstances it is typically just as easy to re-run a circuit or attach a ground to the panel buss.
Please post back and let us know how it turns out....
Last edited by Square Eye; 07-14-2006 at 05:53 AM.