La lista de los repositorios que utilizo en Debian Squeeze (rama estable), sin nada de rama testing o inestable.
Estos repositorios deberían de estar en el archivo sources.list.
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## Repositorios Estables
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## Repositorio de Seguridad.
deb http://security.debian.org/ squeeze/updates main contrib non-free
#deb-src ftp://mirror.unitedcolo.de/debian/ squeeze/updates main contrib non-free
## Repositorio Multimedia.
# aptitude install debian-multimedia-keyring
deb http://www.debian-multimedia.org squeeze main non-free
deb-src http://www.debian-multimedia.org squeeze main non-free

## Repositorio Oficial
deb http://http.us.debian.org/debian/ squeeze main contrib non-free
deb-src http://http.us.debian.org/debian/ squeeze main contrib non-free

## Repositorio Squeeze – Backports.
deb http://backports.debian.org/debian-backports squeeze-backports main contrib non-free
# wget -O- -q http://mozilla.debian.net/archive.asc | apt-key add –
deb http://mozilla.debian.net/ squeeze-backports iceweasel-release

deb http://www.phoronix-test-suite.com/releases/repo pts.debian/

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## Repositorios Varios
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## Repositorio Google.
# wget -q -O – https://dl-ssl.google.com/linux/linux_signing_key.pub | sudo apt-key add –
deb http://dl.google.com/linux/deb/ testing non-free

#HOTOT CLIENTE TWITTER.
deb http://ppa.launchpad.net/hotot-team/ppa/ubuntu maverick main
deb-src http://ppa.launchpad.net/hotot-team/ppa/ubuntu maverick main

# Googel Chrome
deb http://dl.google.com/linux/deb/ stable main

# QGIS
deb http://qgis.org/debian squeeze main
deb-src http://qgis.org/debian squeeze main
deb http://debian.gfoss.it/ squeeze main
deb-src http://debian.gfoss.it/ squeeze main

# QGIS nightly
#deb http://qgis.org/debian-nightly squeeze main
#deb-src http://qgis.org/debian-nightly squeeze main

# ##Chromium
deb http://ppa.launchpad.net/chromium-daily/stable/ubuntu lucid main
deb-src http://ppa.launchpad.net/chromium-daily/stable/ubuntu lucid main

# ## Depôt MultiSystem
deb http://liveusb.info/multisystem/depot all main

## LMDE import
deb http://packages.linuxmint.com debian import

# wine y winetricks
deb http://www.lamaresh.net/apt squeeze main

# VirtualBox
deb http://download.virtualbox.org/virtualbox/debian squeeze contrib non-free

# KDE experimental aptitude install pkg-kde-archive-keyring
deb http://qt-kde.debian.net/debian experimental-snapshots main
deb-src http://qt-kde.debian.net/debian experimental-snapshots main