I see... that just displays the original image at a reduced height/width, but doen't change the actual file size like a real thumbnailer would. hmmmm.... imagemagick or gd would be needed to do it right. A rather simple string-replace could do it the simple way here. The biggest problem would be in making sure when a post is quoted or edited that it re-converts the different thumbs and images to their original version (thumb or image).
