Ooo, these threads are always fun :) I love seeing the reasons behind the names people pick for their finned friends! <3
Lets see...they're on my siggy of course, but I'll give a brief rundown
Ed, Al, Winry, and Hayate are from the anime/manga(Japanese cartoon/graphic novel) Fullmetal Alchemist.
Jirou and Mimiko are from the anime/manga Black Blood Brothers.
Itachi is from the anime/manga Naruto.
Wally is named after Kid Flash, a D.C. Comic character. I originally got it from one of my fav cartoons, Teen Titans, though.
Think I'm a geek yet?
Supernova and Phoenix were both random names that popped into my head upon getting them.
Nami is named after a character one of my good friends created.
And though they aren't listed(because there isn't room....I need to mess with my siggy a bit

) I also have...
Zeus(who is my moms), Hera, Apollo, Artemis, Aphrodite, and Athena. They are all from my current spawn(as is Itachi, actually). This is a funny story actually, after having a random conversation about Greek gods after my friend(same one that named Nami)went to see
Percy Jackson & the Olympians, I just kind of starting calling one of my fav girls Athena.....and it stuck...and branched off from there to Aphrodite, Apollo, and so on
...And I think thats about it for my current bettas xD