Simple bowls are not enough. The water must come from faucets, and the bathtub faucets are particularly popular. Pictured here is cat #2 (Scooter). At least he is willing to wait for his water until mom and dad have woken up; unfortunately, cat #1 (Sophie) thinks it is her divine right to get the wet stuff as soon as the sun rises.
It doesn't look particularly comfortable to me, but then what do I know.