In my opinion Drupal is the best CMS available. It is full featured, scalable, and easy to use. Due to how powerful it is and how large the community is, Drupal can be a bit overwhelming to start. I’ve compiled a list of the best themes available. I’ve only listed themes available for Drupal 6 (though some also work with 5.x and 4.x). Thumbnails are provided by the theme designers.