I am in the process of writing a 40K novel titled "They thought he was a Space Marine but he was a Muffin". It is the story of a space marine who gets killed by a servant of chaos during breakfast. Realizing that its up to him to serve the Emporer and save the universe, the muffin from breakfast jumps in the armour of the deceased marine and seeks revenge. It's full of tense moments where the muffin is plagued by feelings of insecurity and terror as he works amongst other marines, keeping his real identity secret with the visor of his helmet pulled down all the time.

I think I will make a lot of money when it finally gets released.