I am very serious bout search engine friendly design. I came know about "pure CSS". visit - http://www.hotdesign.com/seybold/everything.html Hope this link is working, (it is not opening here) So, we can have such design. Is there anythings else you wana share, please do. Do not comeup with optimizing IMG, Flash, Frame etc.
The link doesn't work. SEO in terms of design is about making sure the text version of your site (no images or JS) is optimised for your keywords.
And of course stuffing as much of the design in css as possible is helpful too, getting your important keywords as high up in the source as possible and using h tags where appropriate.