I've core drilled with water before, what's the difference, besides it being hardened concrete rather than porcelain?
Glass cutting drill bit, eh? Being WV, I should be able to find that... (Glass used to be one of our biggest exports). Do they make 'em as big as 1-1/8"? (1/2" PVC Male Adapter and end of 1/2" PVC LB will have to fit into the hole to make it pretty).