STDU Viewer
STDU Viewer is a free viewer for multiple file formats. The goal of this software is to replace the multiple document viewers with a single simple application. STDU Viewer supports TIFF, PDF, DjVu, XPS, JBIG2 document formats. These are the most popular formats for scientific and technical documentation.
Additionally STDU Viewer supports FB2, TXT, Comic Book Archive (CBR or CBZ), TCR, DCX and image (BMP, PCX, JPEG, GIF, PNG, WMF, EMF, PSD) files.