Malbolge is a programming language designed to be impossible to write a program in. It failed in this aim, because after a mere two years, someone managed to produce a meaningful program (not manually, even then); it took seven years, however, before a "99 bottles of beer"
program was managed (and it's not actually a loop, but just lists the output required).
The Malbolge machine is ternary, just to get you started, and: "Malbolge figures out which instruction to execute by taking the value at [c], adding the value of c to it, and taking the remainder when this is divided by 94", where c is the instruction pointer, [c] being the location pointed to. Also: "After each instruction is executed, the guilty instruction gets encrypted (see below) so that it won't do the same thing next time" - which makes writing loops tricky!
Here are two "Hello World!" programs written in Malbolge:
('&%:9]!~}|z2Vxwv-,POqponl$Hjig%eB@@>}=<M:9wv6WsU2T|nm-,jcL(I&%$#"
`CB]V?Tx<uVtT`Rpo3NlF.Jh++FdbCBA@?]!~|4XzyTT43Qsqq(Lnmkj"Fhg${z@>
(=<`#9]~6ZY32Vx/4Rs+0No-&Jk)"Fh}|Bcy?`=*z]Kw%oG4UUS0/@-ejc(:'8dc
A
more detailed description. I am not suggesting that anyone
really tries to write a program in this, nor even tries to work out how one of those programs works!
(This post could just as well have gone in the pointless thread, but it's technical nature belongs here.)