Answer:
Vikings use this for warmth.
I can be moved. I can be rolled. But nothing will I hold. I'm red and I'm blue, and I can be other colors too. Having no head, though similar in shape. I have no eyes - yet move all over the place.
Large as a mountain, small as a pea, Endlessly swimming in a water-less sea.
What kind of nut is empty at the center and has no shell.
This is needed both for courage and hardcover books.
What gets broken without being hold?