Do they leave a little card with their name each day? At some of the nicer place (non-WDW) I've stayed, they do. If so, could I leave mousekeeping envies for each person at the end of my stay. If so, where should I leave them...the room, front desk...
I will say, that I have never tipped a housekeeper at a hotel, but have never asked for anything "extra" or left the place super messy.