GNU/Linux has a lot of commands. Linux and Open Source Blog lists some humorous (but real) outputs when entered. Below are a few I found interesting
% cat “food in cans”
cat: can’t open food in cans
% nice man woman
No manual entry for woman.
% “How would you rate Quayle’s incompetence?
% ^How did the sex change operation go?^
% make love
Make: Don’t know how to make love. Stop.
%blow: No such job.
$ PATH=pretending! /usr/ucb/which sense
no sense in pretending!
$ drink matter
matter: cannot create