"linux.mng" and "pnglogo.mng" are two sample  MNG animations.  "linux.
mng" was obtained from the official "libmng" source tarball, and "png-
logo.mng" was obtained from:

      http://developer.kde.org/documentation/tutorials/kfile-plugin/\
pictures-kfile/pnglogo-grr-anim-lc.mng