As for Linux, well, I don't think you'll go far there with proprietary programs. But let's assume a .NET like open source initiative. I'd give IE the application a pretty small market share then, but see no problem at all with programs using the rendering engine, i.e. a common "libIE" dependency.
(And, of course, if it actually is the same engine as on Windows, testing alone would guarantee a lot of installations)
[1] http://en.wikipedia.org/wiki/Tasman_%28layout_engine%29 [2] http://en.wikipedia.org/wiki/Internet_Explorer_for_UNIX
While I wouldn't generally praise (any of) the browsers of that time, Macs really didn't have much competition at that time when it came to web browsers.
Huh, really. When was this then? I remember from during my veteran days of the browser wars (2005-2008 or so), IE for Mac was the only browser that PPK (of the Quirksmode.org compatibility tables) actually outright dismissed and at some point stopped testing for. If I remember correctly, his words were "bug-ridden crash-prone piece of trash".
Hey Michelangelo, sign up for my art class and I'll show you how it's done.