Plugin Name: WP Theme Showcase ext and i18n
Plugin URL: http://wordpress.org/extend/plugins/wp-theme-showcase-ext-and-i18n/
Description: WP Theme Showcase ext and i18n (Showcase ext for short) displays uploaded themes with information extracted from the style.css of each theme as well as links to readme files. Showcase ext supports internationalization, CSS-styling, and is highly configurable with user-defined screenshots etc.
A forthcoming version 1.50 has even more options and features.
See also my Danish WordPress portal