Ok, we all know about my fascination with waste treatment (or rather...what happens after the waste is treated). A nuclear power plant in Maryland has honed in on a novel solution: use treated sewage as an industrial coolant.
Now that's not nearly as efficient as pumping the water back into the drinking supply via reservoirs, a la Singapore, but it's a start.
Did I mention I went fishing at the Pilgrim Nuclear Power Plant last week? (Ok, so I walked around on the rocks while Paul and his friend fished, but I did attempt a few casts myself.) Pilgrim uses sea water for cooling, and if you drop a line in the out-take stream the warm water will carry it out to schools of hungry blue fish.