I recently stumbled on a new website, Eclipse Color Themes, and I've been enjoying browsing through the various themes. My favorite so far is the Gedit Original Oblivion by Sepehr Lajevardi. What really makes this theme stand out is that variables passed into a method are underlined. This lets you easily see with a glance where these variables are being used.
The colors are also enjoyable, and care was taken to ensure that every aspect was accounted for. I highly recommend it.