In psychology, it's a common phenomenon: Pareidolia. It describes the instance in which a random stimulus is perceived as significant. For instance in hearing a hidden message (that's not really there) in a record played backwards (even though I am still really convinced that K3 sings about "grote massamoord - godverdomme leuk" if their song "Oma's aan the top" is played backwards - but that's a whole different story.)
The term could also signify interpreting clouds as animals or seeing faces in the moon. Even the famous Rorschach-test bases it's phychological analysis of someone's state of mind on Pareidolia.
Lately, I've come across two very distinct online-cases that are both working with the matter of Pareidolia.
The first one is the strange maps blog. I've already posted something about this blog earlier, but now they've coined the term "cartocacoethes" - which means as much as "the convulsion to see maps everywhere". And they have a small, but nice collection of just that: sh\tains shaped like the USA, a Milanesa in the shape of Africa, clouds shaped like Britain. And this remarkable puddle in the shape of Australia.
The second one is slightly less serious, but all the more hilarious. It's called "inanimate faces", if I'm correct. It's a term for objects that have a face - if you look at it the right way. Like with the one at the top of this post...
There's a nice collection up at boreme.com, and flickr.com has a huge collection of inanimate faces.
Thanks to this website, I've been eyeing my TV for the last couple of minutes, since it really resembles a face with a big smile...