I think you can add an class to the [post_class()][1]
function via Filter; the name, the string can you use form different values: tags or post title?
The follow example use the title of post and add this to the classes of post; if you use the post_class()
function on post tag in markup. Also you can use other values for design this.
function fb_title_post_class( $classes ) {
global $post;
$classes[] = sanitize_title_with_dashes( get_the_title( $post->ID ) );
return $classes;
}
add_filter( 'post_class', 'fb_title_post_class' );