File Roller is an archive manager for the GNOME environment. As an archive manager, it can create and modify archives, view the content of an archive, view a file contained in the archive, and extract files from the archive. File Roller is only a frontend (a graphical interface) to archiving programs like tar and zip.
gThumb is an image viewer written for the GNOME environment. It lets you browse your hard disk, showing you thumbnails of image files. It also lets you view single files (including GIF animations), organize images in catalogs, print images, view slideshows, set your desktop background, and more. gThumb also supports Nautilus thumbnails.