I write and read fanfiction; I have for years.
I've written fanfics for MyVMK (lol), Twilight, Harry Potter, Frozen, The Lion King, Aladdin, Beauty and the Beast, Princess and the Frog, Tangled, Batman, Superman, Iron Man, The Avengers, Orange is the New Black, Pokemon, Sonic, Fullmetal Alchemist, Kelly Clarkson (double lol), One Direction, Jill and Kate (Kelly's backup singers), and I think I've written some Miranda Lambert and Blake Shelton fanfictions too.
I generally only read for Twilight, HP, Frozen, Pokemon, Sonic, FMA, Kelly, Miranda, and Blake, however. I think I've read some DC/Marvel fics, too.