GOM Player

 
GOM is a FREE media player with popular audio & video codecs built-in.

GOM Player includes many codecs (XviD, DivX, FLV1, AC3, OGG, MP4, H263 and more) so you won't need to install separate codecs for most videos. For those videos that require a separate codec, GOM Player will find one.

GOM Player's patented technology enables users to view files with broken indexes or that are still being downloaded.