If you are looking for a high quality, portable, stable multimedia player for MAC OS X, then download VLC Media Player. VLC media supports various formats like MPEG-1, MPEG-2, MPEG-4, DiVX, DVDs, VCDs, mp3,s WAV, ogg and a range of other standard formats.
VLC player is free, and Open Sourced. So you get the source code, which you can use to customize further it to suit your needs.
It can be used in the client server mod to stream and receive network streams. It can stream DVDs, digital satellite channels, digital terrestial television channels on live videos on networks.