FastStone Image Viewer - FastStone Image Viewer is a fast, stable, user-friendly image browser, converter and editor.
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.
digiKam - Professional Photo Management with the Power of Open Source
FastPictureViewer - A hardware-accelerated image viewer for the modern Windows platform.
Flickr - image and video hosting website
DBGallery - DBGallery is a digital asset management cloud service (SaaS) and on-prem web-server software package for a range of team sizes.