Mona Lisa, meet the Mini Lisa.
Researchers at Georgia Tech have made a replica of the Mona Lisa that is thinner than a piece of hair. How? Through ThermoChemical NanoLithography, of course. The researchers used a heated cantilever, which is a device that can create heat-based reactions on a surface. So, where ever they applied more heat to on the surface, the grayer it became; less heat, the blacker. As you can see in the picture, each cell of color looks like a pixel.
The "Mini Lisa" is 30-microns thick: a "micron" is the equivalent to a millionth of a meter. For a little perspective, a red blood cell is about 10 microns in diameter, and your hair is between 10 to 100 microns in diameter.
Here is a life size version of the Mini Lisa:
And here is a much larger version for your viewing pleasure: