Pepper X is now officially the world's spiciest pepper according to the Guinness World Records. However, the person who created it, Ed Currie, has decided not to sell its seeds, making it difficult for people to grow it themselves. Currie says that Pepper X is a patented type, and he won't share its seeds with the public.
Be careful if you see Pepper X seeds for sale on other websites, as they're likely not the real deal.