Yes! I have found a Zen sub-theme for Drupal based on the 960 grid system. I have not checked it out quite yet, but I am going to give it a whirl soon.

Here is the link: http://duvien.com/blog/960-grid-system-zen-sub-theme-drupal-6

For those of you not familiar with grids here is a link to the 960 css grid system. This one is my favorite, I have tried other like Google’s Blueprint and have even created my own. 960 looks the best from a design standpoint giving 20px gutters as the default. Designs as well as HTML build will shine with this grid added in, and make it a whole lot easier when a client wants to change something in the build/after launch phase.

960 Grid System: http://960.gs/

Google’s Blueprint Grid System: http://www.blueprintcss.org/