command line tool for viewing images in X11

 xli can view the following image types under X11: FBM Image, Sun
 Rasterfile, CMU WM Raster, Portable Bit Map (PBM, PGM, PPM), Portable
 Network Graphics (PNG), Faces Project, GIF Image, JFIF style jpeg
 Image, Utah RLE Image, Windows, OS/2 RLE Image, Photograph on CD
 Image, X Window Dump, Targa Image, McIDAS areafile, G3 FAX Image, PC
 Paintbrush Image, GEM Bit Image, MacPaint Image, X Pixmap, X Bitmap.