I had an idea for this while some friends and I were drinking (we're all nerds, so even drunk conversations involve videogames, sci-fi movies and Dungeons & Dragons somehow)
Basically, the world its set in is a high-fantasy world where science and technology have developed simultaneously, but brought to a modern age. Because of magical teleportation and gateways, people don't go to other countries for vacations. Instead, they sign up for "Dungeon Tours". Basically, it's like you're playing an MMO, but in real life: you sign up with a "company", and you get to pick your choice of stuff like job, starting gear and whatnot, depending on what "package" you sign up for (example: a basic "package" is some starting gear, some potions and a decent skill/spell selection, while a deluxe "package" includes a few enhanced items, maybe a magical item or two, and a wider skill/spell selection), go to a level-appropriate dungeon and start killing and looting.
In-game however, you're the CEO of a small upstart "company", and your job is to do what all companies want to do: rise up, expand and corner the market on cheap, enjoyable Dungeon Tours with little-to-no-waiting. Think of it like a Will Wright-type Sim game, but with a definite fantasy-ish bent. Your job covers things like hiring explorers or excavators to find new "dungeons", architects to build new ones, or buying out a competitor's dungeons, things like keeping balance by "seeding" a dungeon with monsters and loot, or maintaining a dungeon by keeping out vandals, predators, vermin and the like. You'd be in charge of even the day-to-day running of the company, handling things like customer complaints/lawsuits, advertising campaigns, payrolls and the like.