ShiftOS
ShiftOS was a game developed by Philip Adams and other developers. The original goal was to go from a bare terminal to a graphical user interface with full desktop features.
Version Changelog
0.0.1 + 0.0.2 (Nov 11 and 12 2013): Hijack screen + Intro to the game
0.0.3 (Nov 30 2013): Knowledge Input, Terminal, Codepoints
0.0.4 (Dec 5 2013): Shiftorium, Clock, Panel, Windows, Close, Program menu
0.0.5 (Feb 14 2014): Shifter, Roll-up, Colour picker
0.0.6 (Apr 9 2014): Program menu icons, Pong, TextPad, File Skimmer
0.0.7 (Aug 22 2014): Image skinning, Artpad, Unity mode, Minimize, Panel buttons
0.0.8 Beta 1.1 (Oct 11 2014): Shiftnet, Calculator, Skin Loader, Audio Player, Video Player, Web Browser, Name Changer, Icon Changer, Skin Shifter, Bitnote, Viruses
0.0.8 (Jan 22 2015): OrcWrite, Minimatch, Downloader, installer, New skinning system, Virus scanner, Shiftnet storyline, Save converter, Labyrinth, System information, Floodgate, and many more (look at forum post)
0.0.9 Alpha 1 (Mar 21 2015): Start menu, Desktop icons, crash screen, scripting