Just an FYI. Did an article on porting the Yahoo Grid CSS over for use with Drupal. It turned out to be remarkably easy to do the 2 column. I have a three column (1/2 or 1/2/3) base page.tpl.php figured out and will by writing that up as well. I know how to do a more flexible 3 column base (1/2, or 1/2/3 or 2/3) but just need to site down and work out all the bugs and write it up in the next week or two as well. I can see 4 column with regions being very easy now too as a next step.
As I get a better understanding of what I am doing I'll convert these to handbook pages.
http://www.blkmtn.org/node/336
Some of the css is sloppy but http://scratch.blkmtn.org is using the Yahoo Grid css now. I will probably be converting my site's theme over to it as well.