Each year, about 1400 American museums follow in the footsteps of the Smithsonian and allow the public free admittance. This year, the day is Saturday, September 28th. Go to the Smithsonian Magazine website and print up a ticket that will allow you and a guest to attend free of charge. If a participating museum is closed on Saturdays, they will honor the ticket on Sunday, the 29th. To find a participating museum, go to their website and choose by the closest to your address, or search by state.