If you have single-lever sink faucets, you can save energy (and dollars) by keeping the lever in the "cold" position whenever it's off. That way, you activate the water heater only when you turn it to "hot". I was surprised to read that even when you leave the lever in the middle "neutral" position, it wastes a little bit of hot water each time you turn it on.
It won't make you rich but every bit helps.
