Swimming in my bowl, eating goldfish food, hiding behind the toy castle in my bowl, reading (mostly literature, poetry, philosophy and science), playing piano, and doing crossword puzzles.
Other goldfish, other aquatic animals in general, and you.
Under the Sea, Tiny Bubbles, the music from Finding Nemo, the music from The Little Mermaid, and La Mer (The Sea) by Debussy.
Finding Nemo, The Little Mermaid, Bedknobs and Broomsticks (because of the underwater scenes), Aquamarine, The Water Horse: Legend of the Deep, Charlotte's Web (all versions), Stuart Little (all versions), the Dr. Dolittle movies (all versions and sequels), and Fantasia.
I like The Undersea World of Jacques Cousteau, anything on the channel Animal Planet, All Creatures Great and Small, and any nature shows relating to fish or aquatic environments.
20,000 Leagues Under the Sea, Moby Dick, The Old Man and the Sea, Bedknobs and Broomsticks by Mary Norton, Mr. Popper's Penguins by Richard and Florence Atwater, Aquamarine by Alice Hoffman, One Fish, Two Fish, Red Fish, Blue Fish by Dr. Seuss, Rabbit Hill, The Tough Winter, and anything, really, by Robert Lawson, The Cricket in Times Square and its sequels, as well as Oscar Lobster's Fair Exchange, by George Selden, The Diary of Anne Frank, Charlotte's Web, Stuart Little, and The Trempet of the Swan by E.B. White, The Midnight Folk by John R. Masefield, the Uncle Wiggily Stories by Howard Garis, the Freddy the Pig stories by Walter R. Brooks, the Dr. Dolittle stories by Hugh Lofting, All Creatures Great and Small, and its sequels by James Herriot, The Little Mermaid by Hans Christian Anderson, fairy tales in which fish play a major role, and nature stories about fish.
Elmo's fish, Alice.