The Drupal theme Zen, that is, not the branch of Buddhism. Earlier tonight I used drush to do some upgrades to this site and in the process the page layout got completely buggered. I use a theme based on Zen (a sub-theme, as it’s called), and it broke. Rob Casson told me that the Zen theme people had made some big changes and it turned out that upgrading Zen from 6.x-1.x to 6.x-2.x pretty much requires that you redo your subtheme. So I did that and things are more or less back to where they were.
I might migrate to WordPress. Drupal is overkill for what I do here. I’ve had the same theme for six years for one WordPress blog and never had the slightest problem with it, either.