Well... this might be cheating... but I am using Space Marines to add fluff to my Necrons... bare with me
The way I see it, Marines can get corrupted by Chaos... so why can't they be corrupted by other things? Like for instance Necrons? Take a chapter like Iron Hands (that pretty much warships the Machine God), and read really far into the fact that the Void Dragon was probably a C'tan, making Machine Spirits an off shoot of Necron technology, and how Ferrus Manus had Necrodermis hands, fill in with a little fluff hogwash of my own about a crafty Harbinger of Transmogrification and we have the Necron Machine Cult. Or Marines that Warship the Necrons has gods.
And now I have my very own Half Marine Half Necrons. Well okay they are still a work in progress...
Peace, Love, and Mass Destruction
Necrons in 6th Edition W: 28 L: 9 D: 5
Orks in 6th Edition W:9 L:9 D:3
F*** that, Barrel rolling monolith all the way.