XnView

XnView is a fast multi-format graphics browser, viewer, and converter. It reads more than 400 file formats, e.g. gif, bmp, jpg, png, tiff, mpeg, avi, and many more. XnView has an Explorer-like viewer that allows quick browsing of directory contents in both thumbnail and preview views. Its features include contact sheets, twain support (scanner & digital cameras), batch conversion, image processing with many filters and effects, and slide shows.