Awesome terrible idea: Lord of the Rings theme park in New Zealand. It would be kind of like Disneyland, in that you'd have different "lands" within the park. Just mirror the locations of the book: The Shire, Rivendell, Moria, Rohan, Galadrial's Wood, Gondor, Isengard, even Mordor. Include some of the intermediary places like the Prancing Pony, Weathertop, the stone trolls, the Bruinen ford, the statues of the Kings, Shelob's lair, etc. Heck, maybe even the woods with Tom Bombadil and the wight barrows. Have a Moria Mine Ride coaster with the Balrog at the end; an eagle flight coaster and if you can hit the crater of Mt. Doom with your ring you get a free ride, etc.
Of course it would cost a butt-ton to build and New Zealand is in the middle of nowhere so you wouldn't have as many customers as you could. I dunno, maybe augment it with a Hercules/Xena theme park.