I'm interested in developing a RPG based on Inception. The team would have a mission similar to the movie, invade several layers of dreams to plant or retrieve information from a target. For the sake of the same, all PCs can enter the next layer of the dream. No one has to stay behind to monitor the dream. Each layer is more f'ed up than the last.
One thing about dreams is you can do things you can't in real life. I want to represent this in the player's skill set. The good little lady might suddenly be an expert thief, but only for the course of the dream.
Are there any existing systems that has mechanics for dreams and reality and how they mesh?