Ginger came with her name, and it suited her.
June came with her name also - the breeder was using months for names with that litter. He died shortly after she came to me, so I felt it would be sorta rude to change it - and so she's still June.
Zippy came with his name also (Rescue).
Bree my husband named - he chose a name that was traditional for a BC, and also was similar to the name of my main character on an MMORPG we play (UO).
I was flattered.
Nick I named. I *almost* named him Rip, but there is some superstition about not naming a dog after a trait you'd NOT like in a sheepdog, so I was afraid he'd be ripping through the sheep. I went through the pedigrees of his father and mother, and "Nick" was the name of a dog a generation or so back. I also considered "Cap" because of his kissy spot (pangea for MP), but it's a common name.