The periodic table is in large part a mystic mystery to those of us without a science background. What is Osmium? Roentgenium? Yttrium? We know these things . . . exist, but we don't know how and we don't know in what form and we don't know where. So filmmakers, game designers, and authors can pretty much make up whatever they'd like, give it a name that ends in "ium," and imbue it with powers, and we'll believe it.
Made-up elements litter every art form, and BuyMetalOnline.com (I know!) crafted this great "periodic table" to gather lots of them in one place. From Flubber to Unobtainium, and a whole bunch we had to look up (turns out Zuunium is a fictional element that gave a character named Timber Wolf superpowers in the DC Comics universe), this table is a survey class in made-up science. Check it out at BuyMetalOnline's site.