Amarok is the music player for Linux and Unix with an intuitive interface. Amarok makes playing the music you love easier than ever before.
Banshee Import, organize, play, and share your music using Banshee's simple, powerful interface. Rip CDs, play and sync your iPod, create playlists, and burn audio and MP3 CDs.
Exaile is a media player aiming to be similar to KDE's AmaroK, but for GTK+.
Rhythmbox is an integrated music management application, originally inspired by Apple's iTunes.
Songbird is a desktop Web player, a digital jukebox and Web browser mash-up.

MPlayer is a movie player which runs on many systems. You can watch VideoCD, SVCD, DVD, 3ivx, DivX 3/4/5 and even WMV movies..
VLC Media Player Cross-platform media player and streaming server. 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.
Totem is the official movie player of the GNOME desktop environment. It features a playlist, a full-screen mode, seek and volume controls, as well as keyboard navigation.
Xine is a free multimedia player. It plays back CDs, DVDs, and VCDs. It also decodes multimedia files like AVI, MOV, WMV, and MP3 from local disk drives, and displays multimedia streamed over the Internet.

Brasero is yet another application to burn CD/DVD for the gnome desktop.
Gnomebaker is a GTK2/GNOME cd burning application.
K3b is feature-rich and easy to handle CD burning application.

gtkpod is a platform independent Graphical User Interface for Apple's iPod using GTK2. It supports the first to fifth Generation including the iPod mini, iPod Photo, iPod Shuffle, iPod nano, and iPod Video.
Gnomad2 manages portable digital audio devices from Creative, Dell, iriver and many others.

Audacity is free, open source software for recording and editing sounds in Linux, Mac OS X, and other operating systems.
Jokosher is a simple yet powerful multi-track studio. With it you can create and record music, podcasts and more, all from an integrated simple environment.