Psychonauts is a platformer from the mind of Tim Schafer (who also created Grim Fandango, Brutal Legend and others), which was released for the PS2, Xbox and PC in 2005. It's a darkly comedic game about Raz, a "Psychonaut" who can enter and explore the minds of other people, helping them overcome their fears and/or bad memories in the process. Though it was a noteworthy commercial flop, critics almost universally praised it, and its cult following has progressively grown over time.
This game managed to appear in 2010's Game of the Decade contest as a 12-seed, losing in Round One to Batman: Arkham Asylum. There was some good news for Psychonauts fans, though: it managed to receive 27.5% of the vote, which was higher than many members of Board 8 expected!