Our house originally had a timer controlled recirculating hot water system. During the winter this recirculator was losing 250 kWh worth of energy per month. I connected switches at each hot water location. Every touch of the switch runs the recirculator for 10 minutes, saving most of the 250kWh / month.
I wish I had installed a second hot water heater at the far end of the home. The standing loss is not significant. I don't think gas or electric fired instant hot water heaters are reasonable solutions.