To view these illusions, look at the thumbnail - you should see the first face. Then zoom in on the image by clicking it - you should now be seeing the second face. If you're having trouble seeing the difference, try squinting or getting your nose really close to the screen.

To have you own mashes featured, please email the image to facemashapp1@gmail.com.

To create your own optical illusions (hybrid images) - download the app here.

A Face Mash (a hybrid image - a type of optical illusion) of Sheldon Cooper and Ned Stark
Uncle Shelley/Ned Stark
I'd like to think I'm a combination of these two people. Probably more Leonard and Sansa though.