SageThumbs - SageThumbs is a powerful shell extension allowing to preview enormous amount of image formats...
MysticThumbs - MysticThumbs generates thumbnails of many image types not natively supported by Windows.
Context Viewer - Context Viewer is an explorer extension in the form of a Control Panel applet that lets you preview...
Pictus - Pictus is a fast, free image viewer that enables Windows to see thumbnails of supported formats, such as PSD. Give it a spin today!
Icaros - Icaros is a collection of lightweight, high quality, Windows Shell Extensions
PicaView - PicaView is the simple, no-hassle image viewing solution.