RealPlayer plays streaming audio and video over the Internet in real-time. It plays RealAudio, RealVideo, MP3, 3GPP Video, Flash, SMIL 2.0, JPEG, GIF, PNG, RealPix, RealText, Ogg Vorbis, and Ogg Theora. It is available for Windows, Macintosh, Pocket PC, Nokia 9200 Series, Nokia 7650, Palm OS 5-based handhelds, Linux, Solaris, and many Unix variants.
Sajber Jukebox is a mpeg layer 3 player with a graphical user interface. It's based on Woo-jae Jung's splay for the audio and QT's graphical library for the interface. The Jukebox maintains pointers to songs on the local system or the net, and when the user wishes to play it, it opens the location and migrates the filedescriptor to the playing process. The advantage of this scheme is that the Jukebox doesn't need to worry about playing the darn thing, and the player won't have to worry about where the song is, since it'll just see the filehandle given to it, and couldn't care less of where it originally came from.