The 'Droste effect' is a Dutch term for a specific kind of repetitive picture, also known by the works of the artists Escher.
An image exhibiting the Droste effect depicts a smaller version of itself in a place where a similar picture would realistically be expected to appear. This smaller version then depicts an even smaller version of itself in the same place, and so on.

These images have been made possible due to the software created by Josh Sommers, who can be found on Flickr.com by clicking the link below.
All regards for his effort on this and making it possible for others to use the technology to create those images.

http://www.flickr.com/photos/joshsommers/378056770/in/photostream/