Phontabulous - Fun, private, secure photo party with your friends
digiKam - Professional Photo Management with the Power of Open Source
Regex Crossword - Welcome to the fantastic world of nerdy regex fun!
XnView MP - XnView is a free software that allows you to view, resize and edit your images. It supports more than 500 different formats!
New Google Photos - Shared suggestions, libraries and photo books
FastStone Image Viewer - FastStone Image Viewer is a fast, stable, user-friendly image browser, converter and editor.