Burning a hole in daylight

That's what my grandmother used to say when we would turn/leave a light on in a room that was already well lit by natural sunlight. The one full on adult/parental activity that I constantly catch myself doing is turning off a myriad of electrical devices behind my family. It's a combination of financial concern (keeping the electric bill down) and environmental awareness that makes me hyper-aware of it, I think, and every time that I do, especially when it makes sense mid-day, I think of her phrase. Funny how things like that follow you through life.