Bottle caps are used as currency in the Fallout games.
A man going by the username GatorMacheteJR
posted on Reddit explaining, with pictures, how he had become such a fan of Fallout after playing the third game that he started collecting every bottle cap he could find. He did this for over seven years. By the time Fallout 4 was announced, he had amassed 11 pounds of them. So, he thought, "I'm going to mail all these to Bethesda and see if I can buy Fallout 4 with them."
Shortly after Bethesda held their E3 conference where Fallout 4 was revealed in full, over 2,000 bottle caps were delivered to their headquarters in cardboard boxes. The man was serious, and he had attracted online media attention in the process through his Reddit posts.
Well...what harm would it do? Bethesda community lead Matt Grandstaff contacted GatorMacheteJR, telling him he would indeed get a copy of Fallout 4 in exchange for the bottle caps. BUT just so no one else got any funny ideas, this was the only time they would be accepting any unconventional currency.
The one piece of information missing from this story is what Bethesda intends to do with all those bottle caps. Buy something fancy with 'em, I say.
