ACDSee - ACDSee is an image viewer that uses very little system resources, and it has a small, sleek size that won't take up much space on your system.
Magnific Popup - The greater part of Lightbox modules will completely preload a picture before showing it.
digiKam - Professional Photo Management with the Power of Open Source
jQuery Lightbox - jQuery Lightbox plugins are utilized to showcase images and other web stuff using modal dialogs.
Flickr - image and video hosting website
prettyPhoto - prettyPhoto is a jQuery Lightbox clone.