MPlayer

MPlayer is a powerful command-line media player.

Streaming Videos From Websites
Mplayer has the ability to stream videos from websites. As a prerequisite, media-video/ffmpeg must have the openssl and gnutls useflags enabled. To do this, simply enter the command mplayer {url} without the brackets

Emerge
Install :

GUI tools
There are a number of different GUI's for MPlayer with different levels of functionality. Some notable ones include:



Disable screensaver while playing a video
Using qdbus (Qt/KDE):

For systems using xscreensaver alone:

See this FAQ entry for more informations.

My video won't play!
MPlayer uses USE flags to enable and disable support for various codecs. If a particular type of file will not play in MPlayer, first check which USE flags MPlayer was emerged with. Update the USE flags to support for the format you are trying to play and recompile.