Brainf**k

Since the question is self-contradictory it's hard to give a serious answer, so here it is:

,[[->+<],]>[<->+<+>--<+>][->+>+[-]>+>+<<<<][->-<]+>[<->[-]]>[->--<----]+>[[---<->+<+>-]<->]>>[+>-<--]+>[[-]<->]<<[->-<-->+++>>>>>+<<<->+<<<+++++[>>++++++<<]]+>[<+>-]++>+<-<->>>>+<<<<->+<+>->>>[<]>[>]<[<[->-<]+>[<->[-]]<]+[>+>+>+>+<<---<<[-]]>>++<<[>>+[+<<<-]>>-<[<]+<<[<<->+]]>[->>+<<]>>[->+<]>[>+++++++++++<-]>[->+>+>+<<<]>.>.>>+>+>+<<<]>[.>>]

Accepts any string or number as input, always outputs "!!!". Have fun figuring out what it does.