Pareidolia is a difficult word for "to see meaning where there is none". Just think of seeing a teddybear in a cloud, for example.
The Face on Mars
Created in 1976
On July 25 1976, the Viking Orbiter 1 photographed the Cydonia region of Mars to find potential landing spots for the Viking Lander 2. One of the photographed rock formations resembled a face. While NASA stated that this was just a random play of light and shadow, UFO buffs were quick to take this as a huge cover-up for alien intelligence. If you click on the enlarged picture, you can see an more detailed picture from recent years.
WTC Devil in the Smoke
Created in 2001
This photo was taken minutes after the second plane crashed into the World Trade Center. Many people claim to see the face of the devil in this (unaltered) photo, complete with horns and all.
