SageThumbs - SageThumbs is a powerful shell extension allowing to preview enormous amount of image formats...
Icaros - Icaros is a collection of lightweight, high quality, Windows Shell Extensions
MysticThumbs - MysticThumbs generates thumbnails of many image types not natively supported by Windows.
FastPreview - FastPreview was created in need of a usable ...
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!
K-Lite Codec Pack - K-Lite Codec Pack is a collection of codecs, DirectShow filters and tools.