I suggest you think of something you are into - video games, collecting stuff, comics, certain TV shows or movies, etc.
Then pick names based on these interests.
For example my family liked a lot of the comic based movies -Xmen, Daredevil, etc. so the dogs have comicbook character names: Jubilee, Storm and Elektra (our dogs)
Just an idea...also makes them easy to remember since you have an interest.