Collect all the dog hair and save it for one fateful day, the old woman is out in her garden enjoying the sunshine, maybe entertaining some guests, perhaps washing is on the line to dry in the lovely sun. The wind is a cool breeze blowing in the direction of her garden, good times are being had by all. Until that is, you promply burn the huge pile of collected dog hair, allowing the cool breeze to gently waft the ungodly smell of burnt hair in her direction. Sit back and watch as she and her guests gag at the stench, running for some sort of refuge from the smokey putrification advancing on their position. Take solice in the fact that her freshly cleaned clothes will stink of burnt hair for many weeks, and enjoy the rest of your day.
Or drain her brake fluid, whatever.