I'm going to also go against the crowd and say Jigsaw. Since you like a puzzle name, you could also consider Rubix as in Rubix Cube. I also like the suggest for scoobie.
Personally, I've always hated common names. I know like 20 Cherokees, Sky, Dream, Star, Gas, etc... I only go for a common name if it means something to me.
But that's just me! I say go with what you love! What do you think would be the best name ever? Pick the name that makes you happy and giggly at the thought. What is are you hoping for in a name? Trust me, everyone will catch on right away with his name and start to love it too.