An obscure scripting language designed by someone oblivious to the fact that in order to get market share, you have to either own the market (in which case people will buy any shit you put out (Visual Basic
anyone?)) or give it away (Perl
, which sucks horribly except for everything else out there).
He coded the entire back end up in REBOL, and I had to look it up to even figure out what the hell it was. Then I laughed at him for picking the most obscure language in the book.