Yesterday I attended the FSharp Dojo: Picasquez and Velasso at Skills Matter in London.
This dojo is all about manipulating images and creating mashups, like this:
My attempt was pretty modest; first I inverted the colours of the Mona Lisa, then I created a pseudo-anaglyph-3D image, which you can see here:
This image was created by taking each pixel from the source image (removing the red) and the pixel twenty places to its left (removing the blue and green) and blending the two together.
You can see more (impressive) results by looking at the photos under the Twitter hashtag FSharp.