I enjoy skinning random sites I frequent – usually open source supporters such as Reddit and OpenCart. As you can tell from ghostCode, I’m a fervent fan of dark themes.
Earlier this year I created a custom stylesheet for http://reddit.com/r/psybient . The subreddit is non-commercial, and I plan on creating a version of that theme which will be openly published with CSS commenting so moderators can learn Reddit’s styles. If you like chilled out music I highly recommend checking the forum out!