VLC media player is a highly portable multimedia player for various audio and video formats (MPEG-1, MPEG-2, MPEG-4, DivX, mp3, ogg, ...) as well as DVDs, VCDs, and various streaming protocols. It can also be used as a server to stream in unicast or multicast in IPv4 or IPv6 on a high-bandwidth network.
VLC plays absolutely anything. It supports an enormous number of multimedia formats, and does not require you to download additional codecs. VLC features a complete streaming server, with extended features like video on demand, on-the-fly transcoding, granular speed controls, frame-by-frame advancement and more. It can also be used as a server for unicast or multicast streams in IPv4 or IPv6 on a high-bandwidth network.
VLC Media Player now features fully customizable toolbars, customizable Skins, supports playback for broken files as well as zipped files, and so much more.
Thanks to Mephistopheles for the tip in Back Page News.