So I was curious the other day about how much money these famous authors actually have. Turns out, some of them are sitting on serious wealth - we're talking billionaires here.

At the top is JK Rowling. Her Harry Potter empire basically prints money. We're talking a billion dollar net worth, which makes her the first author to ever hit that mark. The seven-book series alone sold over 600 million copies and got translated into 84 languages. Then you add the films, the video games, the merchandise - yeah, that's generational wealth right there.

Second place goes to James Patterson. The guy's written over 140 novels since the 70s and his books have moved more than 425 million copies worldwide. His Alex Cross and Michael Bennett series are absolute cash machines. Net worth sitting around 800 million.

Then there's Jim Davis with Garfield. Most people don't realize how much money a comic strip can generate. That thing's been running since 1978 and spawned TV shows, specials, merchandise - all adding up to about 800 million in his pocket.

Danielle Steel is at 600 million. She's written over 180 books and her romance novels basically live on the New York Times bestseller list. More than 800 million copies sold across her career.

Grant Cardone's another one at 600 million. He made his money writing business books like 'The 10X Rule' but he's also running like seven companies and multiple business programs on the side.

Matt Groening, the Simpsons creator, also has 600 million. People forget that Simpsons is the longest-running primetime series ever, so we're talking decades of royalties and syndication money.

Paulo Coelho, the Brazilian author, sits at 500 million. His book 'The Alchemist' became this international phenomenon. Published in 1988 and it's still selling like crazy.

Stephen King is worth about 500 million. The guy's basically the king of horror fiction - published over 60 novels, sold more than 350 million copies. His stephen king net worth reflects decades of consistent bestsellers. 'The Shining,' 'Carrie,' 'Misery' - these are cultural touchstones. And he's still releasing new stuff regularly.

Rose Kennedy was another 500 million, though that was back in 1995 when she passed away. She was the Kennedy family matriarch and wrote an autobiography.

Rounding out the top 10 is John Grisham at 400 million. His legal thrillers like 'The Firm' and 'The Pelican Brief' got turned into blockbuster movies. He's making somewhere between 50 to 80 million a year just from book and movie royalties.

What's interesting is how much of this wealth comes from adaptations. The authors who got their work turned into films and shows made way more than those who stayed in print only. And the ones who created something that became a cultural phenomenon - like Rowling with Potter or Groening with Simpsons - they're the ones hitting the highest numbers.