There Appeared a Trailer Before Stanley. Intrigued, he Watched
The upcoming HD remake of the Half-Life 2 mod The Stanley Parable, has a brand new trailer. Part let's play with a hilariously clueless player, part fourth wall breaking suspenseful introduction to the game, and completely amazing to watch, the trailer is perhaps the only way you could ever hope to introduce people to the core idea of The Stanley Parable without giving a lot of it away.
Anyway, check out the trailer, and keep an eye out for The Stanley Parable HD on Steam, sometime in October.