Barb, my dad's greatest contribution was being frugal with the little things.

He'd go downstairs to do something, see the lights were on, and call whoever was last down there (usually me or my closest in age brother) to come down and turn the lights off.

Drove us NUTS, because he'd then turn them right back on. But I did the same thing to my kids.

As did Husband, their stepdad.