Nominated as a IGF Seamus McNally Finalist, NightSky is an ambient action-puzzle game that offers a gameplay experience unlike any other, as cerebral challenges fill uniquely designed picturesque worlds. The player must maneuver a sphere by using realistic physics to advance; each of these worlds is broken into different areas. The original soundtrack by experimental jazz musician Chris Schlarb will further heighten the surreal experience. IndieGames.com says: "NightSky does things with balls that you never thought possible, and is stunning in motion."
This game is perfect. The art, music, and small background story create a wonderful relaxing atmosphere. The developer never stops changing the gameplay which is always focused around some creative physics mechanic. It runs (on the latest version) flawlessly on linux. I have played through the levels 3 times now and I can't get enough.