Some have and are trying setups similar to what you're describing. I tried it myself a few months back. The results were disappointing.
Some theories are that the water just can't seem to take in cool as efficiently as it gives up heat. The water doesn't stay in the cooling block long enough to get very chilled. I spent nearly a hundred bucks experimenting and trying to accomplish this. I never saw any real advantage in temps or in overclocking ability.
Maybe you can do it better. But there was some guy in Australia who had something like three or four drift 180 watt TECs in an attempt to chill the water. He said the problem was that the water on the hot side heated up faster than the water could be chilled on the cool side.
Don't wanna pour rain on your parade, but you asked.
