Just because your favorite show hasn't been on TV for three decades doesn't mean you can't paint steampunk fan art of it.
And I also have a few fan art paintings of very obvious fan art subjects. The aforementioned Star franchises, Dr. Who, Minecraft and others. Here are some Futurama minis I done did.
But does fan art have to be a movie or TV show? What if you really like former president Richard Nixon and you paint about that? Does that count?
It could be that the artist, Wayne White, isn't really a fan of Nixon. He really enjoys putting words into his paintings. Other words include "BIGUNS" and "Artificial Cherry Flavoring". Now that I come to think of it, perhaps he does like those things.
And finally there is this guy who loves Taco Bell. Specifically, he loves Taco Bell's salsa/sauce (why do I think it's a guy? Dunno. Seems guyish).
Why yes, I do have an Etsy: Fallen Face Studio