Since the game can tell if you're tabbed out in order to reduce the framerate to the background window setting, would it be possible to make it so that if you're alt tabbed out for more than, say, 10 seconds, little Zs start to pop out of your character's head?
Would be nice so that you can easily realize your villagemate is afk and you aren't typing out two paragraphs of the materials he needs all for it to be drowned out by the rest of the party.
Would also just be funny to walk by a village and see the farmer standing around in the fields dozing off.