I won't go into how much I love this show; OK, I'll just state that I really really love it.
These posters were designed by Ty Mattson as a personal project, but Showtime is printing these to be sold on the official Dexter online store. (how cool is that?!) I posted the posters for Season 1 and Season 4 but I wouldn't mind buying all four of them. The rest can be viewed here. Also, I gasped when I saw the packaging below. If Showtime actually goes ahead and releases all seasons with special edition covers, I'll buy all of them in a heartbeat!