Last fall I wrote an article about improving your archives with the Thumbnails for Excerpts plugin. This plugin takes the first screenshot in your article and displays it as thumbnail next to your archives listing. The archives must use the excerpt tag, the_excerpt, in order to display the thumbnail. The plugin also has a number of settings that can be adjusted and a class that can be used in the CSS.
Anyway … now that I’ve added that background information I can move on.