GEGL Earth
I like large images, sometimes I create my own by stitching them together like the ones in my panorama galley. The image I'm using to stress GEGL at the moment is stitched by NASA instead, and is the hugest image file I've got, the image measures 86400x43200px (~11G uncompressed 24bpp)
Two new features were needed in GEGL before I could try to load such a large (larger than RAM) image. Both of them planned since I was experimenting with horizon as a protoype running on my PDA in the beginning of this year. An tiled image pyramid (mipmap) to enable display on screen without needing to access all image data combined with a swapfile backend for the tile system.
Both the swapping and the logic for updating the pyramid needs some further work, swap to gain some more features, the pyramid to be speedier when regions of the backing data changes.
If I am able to find the time to do what I want I should be able to do a GEGL composited, editable presentation about GEGL in the style of the presentation I gave at LGM in Lyon last year for FOSDEM next year.