MysticThumbs!

SageThumbs is a powerful shell extension allowing to preview enormous amount of image formats directly in Windows Explorer by using Pierre-e Gougelet's GFL library (XnView's author).

Extension module for Windows Explorer to render SVG thumbnails, so that you can have an overview of your SVG files.

Pictus is a fast, free image viewer that enables Windows to see thumbnails of supported formats, such as PSD. Give it a spin today!

The FastPictureViewer Codec Pack is a one-stop shop that enables support for 44 additional image formats in Windows Explorer, Windows Photo Gallery, Windows Photo Viewer, Windows Live™ Photo Gallery and, on Windows 7, also within Windows Media Center and Windows Media Player 12, with full 64-bit compatibility. The Codec Pack supports raw formats from more than 350 digital camera models from all top manufacturers and supports CR2, NEF, DNG, SR2 and more, as well as Photoshop PSD and specialists image formats like OpenEXR, Radiance HDR, TGA, DirectX DDS... »

Instant ThumbView is a tiny image viewer that displays image thumbnails in a tooltip window, when mouse pointer is hovered over an image file in Windows Explorer. It supports a lot of popular image file formats, including BMP, GIF, JPEG, PNG, WMF, EMF, TIFF and is very handy for quick image viewing