Thomas Was Alone, the indie platforming game from Mike Bithell, has surpassed one million copies.
Released in July 2012 for the PC and Mac, Thomas Was Alone tells the tale of sentient life emerging inside a computer system represented by polygons and narrated by comedian Danny Wallace. These shapes then navigate the shifting geometry of game world as the player traverses gaps and solves puzzles.
The bulk of the game's sales were in bundles, discounts or promotions, such as the Humble Bundle.
Develop has more details.