I have been messing around with my color scheme ever since I started playing with KDE 4 this summer. At first, I used the “standard” dark foreground, light background schemes that I was somewhat familiar with from my desktop computer. However, after about a month and a half, I discovered that light-on-dark schemes have drastically better readability. So, I tried a few of the dark color schemes on KDE-Look.org, but wasn’t really happy with any of them.
So, over the past week or so, I’ve been slowly building Eclipse, a scheme with (hopefully) high readability. Backgrounds are gray (with active content having a slight hint of blue). Selected items, which have a deep blue highlight, stand out strongly and hovered items are even stronger, as they have a light-blue border.
You can get the theme over at KDE-Look.org.