beautiful vault
n.— «Slot machines are sometimes called “beautiful vaults” in the industry because they bring in nearly three-quarters of the roughly $60 billion in gambling revenue that American casinos generate.» —“Slot Machines for the Young and Active” by Gary Rivlin New York Times Dec. 10, 2007. (source: Double-Tongued Dictionary)
Further reading
Books were rare treasures in the Middle Ages, painstakingly copied out by hand. So how to protect them from theft? Scribes sometimes added a curse to the first page of those books that was supposed to keep thieves away — and some were as vicious as...
It’s hard to imagine now, but there was a time when people disagreed over the best word to use when answering the phone. Alexander Graham Bell suggested answering with ahoy! but Thomas Edison was partial to hello! A fascinating new book about...