Xbox Online (Online Service Revivals): open-source projects that exist because someone reverse engineered a closed product, sorted by GitHub stars.
Launcher for Xbox recompiled games with replacement Xbox Live online services
Dashlaunch plugin that re-enables Halo 3 matchmaking on Xbox 360 through custom servers
Unofficial online server for Forza Horizon 2 (Xbox One build) on PC
Disables Xbox Live blocking code in original Xbox BIOSes for Insignia
Xbox 360 plugin that redirects Halo 3 matchmaking to custom servers
Community edition of Marble Blast Ultra from Xbox 360 Live Arcade
Chromehounds server for Xbox 360 netplay in Xenia