Don't forget Win3.x. I remember working on that, trying my hand at OS/2 Warp with high hopes. I never used NT, just the home version of Windows 2k, however I was already trying to move away from Microsoft at the time. I was introduced to AT&T Unix in the late 90's with our Audix voicemail system, and learned a lot while attempting to upgrade the hardware to a more current 486 computer. I got hooked but Unix was expensive as hell, then the internet led me to Linux. My first attempts were with a version of Slackware that ran from a folder on the Windows desktop and by '99 I had my first dedicated server up and running. It wasn't until 2006 that I finally dumped my dual-boot desktop and permanently dropped Windows.