VLC (initially VideoLAN Client) is a highly portable multimedia player for various audio and video formats (3GP, MP4, FLV, AVI, WAV, MKV, ASF, VOB, AAC, WMA, MPEG-1, MPEG-2, MPEG-4, DivX, mp3, ogg...) as well as DVDs, VCDs, and various streaming protocols.
Foobar2000 is a free audio software which is likely to please those looking for a greater measure of control over their audio players. It comes with the powerful equalizer and resampler are particularly impressive.
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.
Winamp is a free multimedia player made by Nullsoft. It supports numerous audio and video formats. It also plays streamed video and audio content, both live and recorded, authored worldwide.
GOM Player is a free multimedia player with popular video and audio codecs built-in. GOM Player supports file formats such as AVI, DAT, MPEG, DivX, XviD, WMV, ASF.