How to play RMVB files in Ubuntu

Tested And It Works ( TAIW)

Step 1 :
At the top panel , Applications >> Accessories >> Terminal

Step 2 : Adding Medibuntu repository to your list
Enter this Code ,

sudo wget http://www.medibuntu.org/sources.list.d/gutsy.list -O /etc/apt/sources.list.d/medibuntu.list

Step 3 : Adding gpg key
Enter this Code,

wget -q http://packages.medibuntu.org/medibuntu-key.gpg -O- | sudo apt-key add - && sudo apt-get update

Step 4 : Install Mplayer
Enter this Code,

sudo apt-get install mplayer

Step 5 : Update / Downloading Codecs
Enter This Code,

For 32 bit
sudo apt-get install w32codecs

For 64 bit
sudo apt-get install w64codecs

Hope it helps =)