The Champion Skull will give experience points to the commander who carries it. Not a huge amount, but a steady trickle every month.
I don't think the Skull is so great. Most of my commanders seem to earn plenty of experience on their own, and I always have other uses for my Death mages & gems. But feel free to try it for yourself!
Edit: Ninja'd by vfb that time. Wow, y'all are fast!
