IBM's OS/2 and OS/2 Warp operating systems.
More Microsoft Dirty Tricks History
Sun, 13/07/2008 - 8:32pm — HomerIn the wake of the death of Joe Barr, Linux.com's editor, I've been reacquainting myself with his work, and his insights into Microsoft's earlier "dirty tricks". I was vaguely familiar with some of this, but it's worth remembering that Microsoft's racketeering techniques are hardly new ... they've been doing this stuff since day one.
I may end up adding this to the collection at Grokdoc's Dirty Tricks History wiki pages, but for now - here's a sample: