My anery has been christened Sterling, because, when she's not in shed, her scales are a beautiful deep black and a gray that is really so sparkly it's silver. So she was named by appearence.
Dogs... we had K.C. Our last name begins with K, and the C stood for critter. Plus, "Casey" is Scotch-Irish and he was a West Highland White Terrier. Now, my mother has a Scottish Terrier, whose name is Oliver. My mother named him. Once I have a house, and am settled into it, I'll likely get a dog myself, a female Australian Shepherd. I currently like the name Sydney for her.
Another good snake name that I really like (and I think would suit a nice Ball Python, or a boa) is Malaki [Mal-uh-kie]. Got that from one of my students when we had a name-the-frog contest. I let them propose names, and then vote on the ones they liked best. So now, the African Clawed frogs are Dilbert and Lily.
Who else? I name some of my fish- bettas and other fish I can tell the difference between. I have had Azure, Benji (named by my Sig. other- after the guitarist in the band Good Charlotte), Caspian, Blue (I was 10- leave me alone!) and the best, named by my mother- Darth [Betta].
Other fish- Cash, the cichlid, cost me $10 in college and was, at the time, the most pricey fish I ever bought. Poseidon, the Bichir, named by my S.O. who is fascinated with Greek Gods. Mike and Little Mike were Corydoras cats. I have two current Kuhli Loaches- Kuhli-O and Joe Kuhli.
A Cavy was named Abby, but went by "Piggy." Gerbils- Dorothy, Dilbert, Dexter, Dottie, Charcoal, Boo, Roo, Digger, Noelle, Ebony, Olivia, Sophia. Hermit Crabs- Ninji, Shy Guy (both from Nintendo's Mario Bros.), Pigwidgeon, Cooper, and numerous others who I have long-since forgotten. Birds- Toby (a Cockatiel), Winston (a.k.a. Winnie, a parakeet), Sam (a 'keet), Fred (a 'tiel), Buster (a parrot- my moms)... probably many others too that I have since forgotten.