Some people will just get out the flyswatter. But not me. To me, flies aren't just disgusting; they have a whole other side. If there is a fly in my house, I will try to catch it and take it outside, except when it is extraordinarily cold. Then I will move it to a safe place, train it, or just help it in any way that will not break many rules. I observe flies, like to watch them, and discourage killing them.