Illustrator, designer, and all-around creative person Mark Hofmann made this model of General Grievous (Revenge of the Sith) out of pieces of Warhammer 40K models. At the link, scroll down past the pictures for rules that Hofmann has improvised for playing Grievous in 40k.

Link via Geekosystem | Photo: Mark Hofmann | Previously: Excellent General Grievous Costume