Water, water everywhere, and not a drop to waste.
I borrowed this from Cool People Care:
Whether you don't feel like finishing your glass, or accidentally drop some ice cubes on the kitchen floor, don't pour good water down the drain. Most of us have the luxury of clean and reliable water whenever we want, but we can't take that for granted by letting it go to waste. See if your pets or plants want that extra water before you empty it in the sink.