When I was heavily into animal conservation and photographing wilflife many years ago, I was snapping some photos of a bird in the nearby swamp.
After getting the photos developed and scanned, I sent the pics to a collegue of mine. A few days later, she said there was something strange in one of the photos. Keep in mind that I didn't see anything while taking the pictures, and I didn't notice anything strange about it before either.
Anyway, she touched up the picture through adobe or some other photo enhancing picture, which basically enhanced the outline of this "thing".
At first, I thought that she had planted/manipulated the photo, to add this weird looking thing to the pic. But after further examining the original photo, the same exact outline was in the original, just more faint.
The closest thing I can explain about what this thing looked like was a deformed baby with broken wings. I pondered this just being the way the sunlight went through the forest, creating this image, but the outline was so perfect that I just couldn't accept that as what it was.
A lot of my Christian friends told me that I should not try to figure out what it was and that I should not send it to anyone else, or I'd be asking for trouble, but I then sent the a copy of the original photo, along with enhanced photos to several people. The very next day, the hard drive myteriously crashed.
I don't know if that was a sign not to mess with it any more or not, but I haven't sent anyone else any photos since then. Although I've mentioned it to people several times in the past, not many people believe it.