Well gore,
midnight commander (mc) is a ripp off of norton commander..
and in that sence yes.. Windows 1.0 and Windows 2.0 were crappy clones of nortons great toolkit..

The worst OS I ever used was proppably windows ME..
pre-installed on my parents PC, they didn't even give me the WinME CD, it had a recovery thingy . . utter crap !!