Our day-after-Thanksgiving tradition is to collect up all the things in the house that we haven't touched in a year, and donate them to Goodwill. DH and I actually do this all year long, but Black Friday is the one day that the kids have to take a good hard look at their toys and books and decide if these are things that another less fortunate kid can get some use out of.
This is our third year doing it. They resisted the first two years, mostly donating small, junky things (a single Hot Wheel here, a McDonalds toy there). But this year they really went wild! We took in three huge boxes of old toys and books, and now their room is super clean and has loads of space.
It feels great to have stuff leaving the house on Black Friday instead of entering it. Now to get the tween to think something other than, "Great! More space to fill up with new toys and books!" :)