This tutorial shows how to add medibuntu sources to ubuntu repository.So there will be more free softwares available.
By now,medibuntu includes following binary packages:
# aacgain
# aacplusenc
# acroread-fonts
# alsa-firmware
# amrnb
# amrwb
# app-install-data-medibuntu
# apport-hooks-medibuntu
# gizmo5
# googleearth-data
# googleearth
# hot-babe
# ices
# libamrnb3
# libamrnb-dev
# libamrwb3
# libamrwb-dev
# libavcodec-extra-52
# libavcodec-unstripped-52
# libavdevice-extra-52
# libavdevice-unstripped-52
# libavfilter-extra-0
# libavfilter-unstripped-0
# libavformat-extra-52
# libavformat-unstripped-52
# libavutil-extra-49
# libavutil-unstripped-49
# libdvdcss2
# libdvdcss-dev
# libpostproc-extra-51
# libpostproc-unstripped-51
# libswscale-extra-0
# libswscale-unstripped-0
# medibuntu-keyring
# non-free-codecs
# realplayer
# rmconverter
# w32codecs
# w64codecs

Step1:Edit /etc/apt/sources.list file by this command (open terminal from Applications->Accessories->Terminal to type command):

gksudo gedit /etc/apt/sources.list

append following code into the end of the file(for ubuntu9.10):

deb http://packages.medibuntu.org/ karmic free non-free

change karmic(ubuntu 9.10)in previous code to hardy/intrepid/jaunty/lucid(ubuntu 8.04/8.10/9.04/10.04).

Step2:Use this command to add GPG key:

sudo apt-get install medibuntu-keyring

update your system:

sudo apt-get update

Done.Now,you can install the packages list in the top by apt-get install command or from synaptic package manager