Windows Xp: Version 19.914 =link=
One alleged email from 2007 (never verified) quotes a senior developer: "If someone asks for version 19.914, tell them it requires a TPM 19.0 module and a holographic storage drive. Then watch them try to find it."
Over the years, a small community of retro-computing fans and creepypasta writers have invented a feature list for the mythical OS. These are not real, but they are entertaining: windows xp version 19.914
It never passed any Microsoft QA process. It never shipped on a CD. It never received security updates. One alleged email from 2007 (never verified) quotes