I heard about this from Southern Savers but was pretty skeptical that there would be anything in my area participating. I am so glad I was wrong. It seems our local Edison & Ford Winter Estates is included and they are normally very expensive. So check it out and see what's open in your area!
On September 26th for annual Smithsonian Museum day, you can get FREE admission to many museums throughout the country. You will need to go here and register to get your free admission pass.
To see a list off all participating museums go here.