VLC Media Player 1.0.3
Play audio and video files in real-time and streaming modes.
Price : Free
Operating system : Windows 2000/XP/2003/Vista

Publisher's description :
VLC (initially VideoLAN Client) is a highly portable multimedia player for various audio and video formats, including MPEG-1, MPEG-2, MPEG-4, DivX, MP3, and OGG, as well as for DVDs, VCDs, and various streaming protocols. It also can be used as a server for unicast or multicast streams in IPv4 or IPv6 on a high-bandwidth network.
What's new in this version :
Version 1.0.3 includes new deinterlacers modules based on yadif and yadif(x2) algorithms and fixes downmixing of particual 4.0 AC-3 audio tracks.