It's not the clown I find creepy (never have been afraid of clowns) but the two people in the background with their backs to us are intriguing. Reminds me of an old ghost photo I saw several years ago. Ooh! Speaking of which, here's a ghost photo (not the one I was just talking about, though) which has always creeped me out:

The photographer who took this picture was visiting her mother's grave at the time. The man in the front seat is the photographer's husband. The person in the back seat, wearing the glasses -- is her mother.
Since it was taken back in the 50s, this is one of a number of ghost photos considered to be authentic, having been studied by experts in several fields (including science, photography and the paranormal) and to date, they all agree the photo shows no signs of having been tampered with or altered. No smoke and mirrors, no camera tricks, no double exposures, no faulty film stock. As far as experts are concerned, there's no way this photo could have been faked.
Pretty cool, huh?