OSNews

At our highschool, the choice was between Commodore PETs which could only run Basic and use floppies only, and the ICONs, which could run C, Interpreted Pascal, Logo, UNIX shell scripts, and a few other languages, and provided a shared Unix-like home directory structure on a central hard drive, and provided some cool animation and drawing packages, there was no contest at our high school. The ICONs were favoured by a large margin:
http://en.wikipedia.org/wiki/Unisys_ICON

Now the machines did have their problems. The first of which was that it was possible for some of us (4 people, to my knowledge) to gain root access through a few silly security holes. Fortunately it was an unwritten code at the time that no root user would abuse his power to cheat on assignments, so the teacher turned a blind eye to it (possibly since OSes like Linux didn't exist at the time to provide eager future programmers a way to learn). But this exploring of how QNX ticked occassionally lead to problems. For instance one annoying thing on QNX was that it was possible to create a file that was non-deletable, non-readable, and non-writable by everyone including root. Basically dead disk space that could only be removed by reformatting.