This can get downright evil if you make use of Human Heritage. Then, regardless of templates, you type would revert back to Humanoid (Human). Thus, any template that could be applied to a humanoid can be applied infinitely. Thus making a Vampire Lich Gravetouched Ghoul Spawn of Kyuss Death Knight Human a legitimate creature (admittingly, one which would have had to have a heck of an interesting life/unlife). Honestly, given the existence of LA, most of this wouldn't really be practical anyway, other than as a hilarious thought experiment as to how such things come to be.