The Great Dilithium Crystal Heist

Dilithium crystals were invented by Star Trek's producers as a plot point for an early episode; there is a real-world molecule known as dilithium, but it doesn't power starships (so far as we know).

Apparently dilithium crystals are rare and valuable in the DC universe too, as seen in this early 70s issue of Justice League of America. Here Hawkman, in his role as a police officer of the world Thanagar, rushes to apprehend a thief of the legendary crystals. Oddly, he's stealing them from a museum. Perhaps they were the very crystals first seen in "The Naked Time," preserved by Thanagarian historians for posterity. Well, except this story takes place in the 1970s and the Star Trek episode occurs in the 23rd century. On the other hand, it was a time travel episode, so...