Braid

From the game's official site: Braid is a platform game in a painterly style where you manipulate the flow of time to solve puzzles. Every puzzle in Braid is unique. There is no filler. Braid treats your time and attention as precious. Braid does everything it can to give you a mind-expanding experience. All Braid's gameplay is based on time manipulation. Journey into worlds where time behaves strangely: observe, learn from, and then master these worlds.