Quadrilingual Crazy Programming

mtve writes: "Have you ever seen source code that is valid on four languages: Perl, C, Befunge, and BrainF*ck? During last Perlgolf season famous Perl hacker Jérôme Quelin submit such inconceivable masterpiece and now he published expanded explanation of his solution. Caution: that text can hurt your mental health. Play Perlgolf!"