Kaleidoscope is an Espresso theme using a dark background and vibrant colors, inspired in Kaleidoscope app website by Sofa.
To the moment, I just focused into improving HTML and CSS styling. However, I found this a very pleasant experience, and probably find myself adding some more stuff for Javascript, PHP, Markdown and maybe Twig.
You can contact me at Twitter.
Special thanks to Anthony Short for letting me use Quiet Light as a base for this theme.