Loading the car with donations for a massive Habitat for Humanity yard sale: The good feeling of clearing the house of things from an ex-boyfriend which I hadn't felt right about just tossing (working toaster oven, blanket, comic books, etc.).  Also just lightening my kitchen up by giving away some tools I haven't used in a year, making it easier to find the ones I want.  I know this doesn't work for everyone but I'm happy about it today.