Blogging Pro had an article last week regarding optimizing CSS files in order to achieve a faster page load. I know a lot of the time removing whitespace can kill a lot of the file size. Of course it makes it difficult to edit later but for production use there are several programs out there to reduce whitespace for you making a smaller file size.
Many of these programs do much more than remove whitespace. It also condenses CSS into shorthand forms and only includes the necessary elements in each CSS modifier.
The thing about this article that surprised me the most is that the best program they choose does a very good job at its task. Another thing that is popular is compression on the server side. It does tax the server somewhat but I have found compression to be much faster.
Nevertheless, this is a pretty good tutorial to try and see if it does make a difference or not on your site.
