If I am going to use it, I nickname it. Nicknames are always "Mc_____", with Emboar's "McSizzlin'" being one of my favourites, as well as Luxray's "McKitykatz" in platinum or Ampharos' "McBaaz" in SS, Black and Black 2 --- Ash Ketchum is a Timelord; he never ages! That or a vampire...
I name them (As closely as possible, anyway.) after various anime/game characters.
Like, for example: 1. Poliwag named Suwako (Touhou) 2. Seviper (Or Arbok) named Kanako (Touhou) 3. Ralts named Satori (Touhou) 4. Hitmonchan named Domon (G Gundam)
Before anyone says anything, I like Touhou games (And fangames) in general. --- Currently Playing: Pokemon Black (US), The 3rd Birthday (PSP), Final Fantasy IV: The Complete Collection (PSP), The Binding Of Isaac (PC), Spelunky (PC)