Successful blood drives have ranged from the Heinlein Society's efforts to, starting more recently, the drives that tie into the release of each year's Saw film (which is not my thing, movie-wise, but I know several fans of it).
Now I think the producers of True Blood could and should sanction blood drives. I think there'd be a market for that.
The show gets lots of people's blood flowing: some of that blood could flow to the Red Cross...