wireless domestic hot water circulation

I'm convinced that circulating hot water, even when controlled by a timer or aquastat, is a big energy-waster. I still find the circulators running 24/7.



I'm intrigued by using wireless technology, with motion sensors in the kitchen and bathrooms.



Would like to know what products are the best and what kind of energy savings you've experienced, plus and "do's-and dont's".



Thanks.