"Ghosts now official exist" is the title of this piece on a form of digital photography. That's "computational rephotography". Sergey Larenkov is a master of this stuff, smuggling WWII into the present.
This one chills me every time I see it, not just a ghost walking today's streets, but two ghosts carrying their own dead, ghosts themselves already haunted:
(via Andrew Plumb via Twitter)