It originates from the WotC character optimization boards, where it was first used as the name of a hypothetical character implementing the most broken build ever to grace the forum. It revolved around the Sarrukh's 'alter form' ability, with a kobold and his familiar/psicrystal/whatever gaining access to it somehow (there are multiple methods) and more or less instantly achieving omnipotence by abusing it. Effectively infinite ability scores, every feat and special ability ever printed, etc. The short name caught on when referring to it in discussion, and it came up often because really, what tops it?
--Impeesa--