To be honest to you i think that a mythological name is a MUST.

I had a black cat Frida.

now i own:
- A dog Osiris.
- Ferret Ares (i call him Muad'Dib - since he IS the "small mouse"
- Cat Behemoth (asctualy for those familiar with Bulgakov's "Master and Margarita" it's actually Begemon :D which in russian also means hippo)