My son and wife has named all of ours
Betta - Twinkle Little Star
Gouramis- Roxas, Sora, Fire, Ball
Red Wag Platy- Emp
Tetra - Marco (sadly Polo died on the way across country)
Clown Knife- Sword
Gudgeon - Beluga
Ray - Pep
I know one of the Corys name is Bob, cant remember the rest.
My Wife would kill me if I forgot her pride and joys
Koi - Ricky Retardo (dumbest fish I have ever seen, but I think he might be blind because he runs into everything at full speed all the time)
O-Ushi (OK I named this one, I just like that name and it looks like a japanese flag with only one red spot on its head and the rest being white)
Specs (just a spotted goldfish)
Goldie (and just a goldfish)