Gnump3d is an easy-to-use and free streaming media server for Ubuntu Linux. It allows you to watch and navigate through your media collection via web browser. Since it has a browser interface, watching and sharing media files across the network is a piece-of-cake. More here

It was mainly developed to support mp3 files but now also supports various other audio formats, such as, wav, ogg, au, and mpc. Installing and using gnump3d is quite easy.