I'm reading "Devil in the White City" right now. I posted about it a couple of weeks ago.
Nikola Tesla's name is mentioned several times in the book as if he were famous and influential. I'd only heard the name in the movie "The Prestige" and asked several people if they knew who he was. No one had heard his name.
The mystery is now solved, and he is my countryman.
He was a Serb born in Croatia just before the civil war here in the USA (since I was born in the States, my ancestors were his countrymen). Eventually, he came over here and became the most famous scientist and inventor of the late 1800's and early 1900's. He is most famous for his work on electrical currents and for inventing the radio. Long story short, his alternating current (AC) method was better than Thomas Edison's direct current (DC) method and now we use Tesla's AC to light our homes, power our laptops, etc.
He was pretty eccentric, having an obsession with pigeons, having a superstition with the number 3, and tearing up the contract with Westinghouse that would have made him the world's first billionaire.
He is sometimes called, "The man who invented the Twentieth Century."
Nikola Tesla, another random person to know.