I actually wouldn’t call myself very active in any of these fandoms these days. I just greatly enjoy the titles in question. Though I have gone as far as having fan-characters for a select few of them.

Alien

Aliens vs Predator

Black Lagoon

Digimon (The first three shows and the monster designs.)

Disgaea

Doctor Who

Gurren Lagann

Fallout (3 and New Vegas. Can’t get into the gameplay of the others.)

Mass Effect

My Little Pony: Friendship is Magic

Panty & Stocking with Garterbelt

Pokemon (The games exclusively.)

Predator

Torchwood

Transformers (Beast Wars, Animated, War for Cybertron, and Prime. I really can’t get into the others, especially the Japanese stuff.)