Mattress Flipping - Flip over and rotate.  If you have a pillow top, just rotate.

Filters - Check and change, if needed, AC or furnace filters.

Fire Drill - Make sure everyone in the house knows what to do in case of an emergency.  Run through a practice fire drill.  A meeting place is very important, this should be outside of the house and away from any emergency personnel.  A great place would be a neighbors porch.