Windows codename Longhorn is, without a doubt, the most visually-exciting time in Windows development. With planning for the OS beginning ~2000 and ultimately ending in 2007 as Windows Vista, it saw the end of the Jim Allchin era of Windows and ushered in one Steven Sinofsky, who was recently let go of after the completion of Windows 8.

Until its cancellation and reset in 2004, Windows Longhorn was an overly-exciting prospect for Windows enthusiasts and developers. Instead of dividing users and forcing a completely newfangled UI upon its users, Windows Longhorn sought to extend and enhance the familiar. While Windows Vista may have looked close enough to Longhorn, it was nowhere near it to those of us who grew along with Longhorn through its early years.

With the news of Steven Sinofsky leaving Microsoft , I am once again excited by the prospect of what's possible for Windows. With this gallery, I seek not only to demonstrate the evolution of a the most exciting UI Microsoft has ever envisioned for Windows, but more importantly, to convey some semblance of the enthusiastic passion developers and users had for Windows: a passion long since lost that I think Microsoft should focus on reclaiming.

So with that, grab a cup of coffee, sit back, and click-through to see a vision of Windows you either forgot about or have never even seen.

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