The Pix image gallery is ideal for browsing and displaying a collection of images.
Gidak-on
An Image gallery application.
Gwenview
Gwenview is a fast and easy to use image viewer by KDE, ideal for browsing and displaying a collection of images.
KPhotoAlbum
If you have hundreds or even thousands of images on your hard drive, it becomes impossible to remember the story behind every single image or the names of the persons photographed. KPhotoAlbum was created to help you describe your images and then search the big pile of pictures quickly and efficiently.
GThumb
gThumb is an image viewer and browser for the GNOME Desktop. It also includes an importer tool for transferring photos from cameras.