Intellij_color_schemes is a project mainly written in ..., it's free.
collected color schemes
A collection of IntelliJ themes that I use from around the web.
They should work with most IntelliJ products. I've tested with Idea, RubyMine, PhpStorm, PyCharm for most.
I've forgotten where I found some of these, but I've provided links to the ones I could remember below.
blackbored.xml
solarized by jkaving https://github.com/jkaving/intellij-colors-solarized
Dark Pastels.xml by Ted Wise http://tedwise.com/2009/02/26/dark-pastels-theme-for-intellij-idea/
Vibrant-Ink.xml by eed3si9n https://github.com/eed3si9n/color-themes/tree/master/IntelliJ-IDEA/Vibrant-Ink