Just spent some time watching a video at Nettuts (http://net.tutsplus.com/videos/screencasts/a-detailed-look-at-the-960-cs...) demonstrating the 960gs (http://960.gs) system for rapid CSS development. It is a small framework that offers really quick layout options. The question is, is it worth it for Drupal?

There is a 960gs Drupal theme available (http://drupal.org/project/ninesixty) but personally I think I will stick to Zen for now as I know it so well. It seems a really well developed project though so have a look.

If you are creating CSS layouts from scratch then I definitely recommend looking at the 960gs system.

The sketch sheets and templates really help speed things up and can help all those invested in the site (designers, developers, managers) with understanding how the layout works.