While I didn't love Capcom's Dead Rising as much as some—I thought the demo was cackle-inducing genius, but hated the punitive advancement system in the full game—there was no doubt that it was inspired carnage. Inspired by the Dawn of the Dead movies, clearly. I mean, it's set in a mall filled with zombies. It may not have ripped off the plot, but it clearly borrowed its setting, and to great effect.
Unfortunately for Capcom, the producer who holds the rights to the Dawn of the Dead movies didn't like their homage and is now suing them for intellectual property infringement.