KoolPlaya will play any video file if you have the appropriate codecs installed and has lots of features.
Features:
* supports every VfW-Codec out there and lots of formats like xvid, divx, avi, mpg, mpeg, mkv, wmv...
* free zoom + fullscreen
* customizeable interface
* screenshot function
* import extra audiotrack
* easy internet-update (klick help -> update)
* loop + partial loop
* multi language support (deutsch, english, espanol, francais, galego, italiano, magyar, nederlands, polski, russian, slovak)
* no installation requiered
* 159.5 kb small & only one file
* easy to use
* 100% free!