It would be really nice to have an option in the thematic-theme to manipulate the posts_per_page-variable for archive-pages. With the current files (archive.php, category.php, and tag.php) it is not more than this:
archive: get_header(); query_posts('posts_per_page=NUMBER_OF_POSTS');
category: get_header(); query_posts('posts_per_page=NUMBER_OF_POSTS&cat=' . $cat);
tag: get_header(); query_posts('posts_per_page=NUMBER_OF_POSTS&tag=' . $tag);
Defining the number of posts for these three pages (or, eventually for all the paged-pages) would make it much easier not to always add half of the files to one's own theme!