MPlayer (a popular video player for linux) package for maemo. A simple GUI is also included. Provides the best playback performance for mpeg4/divx/xvid video on Nokia 770/N800, can use subtitles.
UKMP is a media player. It focuses on fast response, ease of use and visualizing your music and video collection in an intuitive way. UKMP requires python (and mplayer for videos). Includes UKTUBE.
Kagu is a playlist based music player with A2DP and maemoscrobbler support, finger friendly inertial scrolling, theme engine, and intelligent screen/battery usage optimizations.
MediaBox is a media center for the N800. Features include: mplayer embedded, video player with video thumbnails, music player with album cover art, image viewer with image thumbnails, FM radio, smooth kinetic scrolling.
Streamtuner (maemo port) is a point-and-click GUI browser for the thousands of Internet radio streams available today. It lets you play streams and manage your favorites in a single window -- like a Linux tuner for Internet radio.