Dull, boring people would just take a picture of themselves and let it stand at that. Nerds on the other hand will have their head exploding with possibilities. A creepily lit image of Cthulhu taken from my statue? A pattern that produces shimmering rainbows with a television's comb? A renaissance painting of a religious icon? A picture of a Jack Kirby drawing of Galactus?
Instead I decided on this:
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For those who don't recognize this it is a screen shot of Adventure for the Atari 2600. It's most famous for being the first game to include an easter egg. That particular image is a rather dramatic one of the game since the player (the yellow square in the middle) is about to be eaten by a dragon (the red duck).
Actually getting the image into XBox Live was annoying. I had to color correct the screenshot so that the colors would be particularly vibrant, print it out at a high DPI, and then hold the camera and paper steady with decent lighting to get the picture. The square I have above is roughly the chunk of the screenshot that became the icon.