I like writing code. :)

Did you come here looking for an image based on prime numbers? https://www.dropbox.com/s/hgihjjn2kb13o9s/Ulams_Ant.png

Or how about a giant Ulam Spiral? https://www.dropbox.com/s/6adp9a0u3g66ei4/Ulam_Odds_10MillionInts.png

What they are: The top image is Ulam's Ant, like a mixture of Ulam Spirals and Langton's Ant, an ant is placed at the center of the screen. As it moves, it counts by 1. It moves straight ahead on composite numbers, but turns on Prime numbers.

The bottom image is a giant Ulam Spiral, but counted by +2's, so it is an Ulam Spiral comprised of only odd numbers.

They're large; you can view the originals in full detail by right-clicking the image preview and selecting download original.

Here's a very colorful one. it involves turning by 45 degree angles on primes. https://www.dropbox.com/s/7m9ihgfvm32psbz/Ulams_Ant_stepB1p1.png