FastStone Image Viewer - FastStone Image Viewer is a fast, stable, user-friendly image browser, converter and editor.
FotoSketcher - Turn photos to paintings, drawings and sketches. FotoSketcher is a 100% free program to turn your photos into beautiful art, automatically.
Photoscape - high quality photo editing software, that enables you to fix and enhance photos.
Elfin Photo Editor - Elfin Photo Editor is a handy program that enables you to make your photos shine.
IrfanView - IrfanView ... one of the most popular viewers worldwide.
Magic Photo Editor - Magic Photo Editor for Windows is a feature-rich application that allows you to create original edits of photos.