Packages that I have that you don't.

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abs
acetoneiso2
addon-sdk
aircrack-ng
akonadi
allegro4
alsa-firmware
apr
apr-util
arandr
arj
arpack
asciiportal
aspell-en
at
at-spi
audacity
automoc4
bamf
banshee
bash-completion
bc
blobwars
blobwars-data
blueman
blueproximity
bluez-firmware
boo
bridge-utils
brlcad
brltty
buildgen-git
buildgen-selfbuild-git
bullet
bwidget
bzr
cairo-dock
ccache
cgminer
check
cheese
chromaprint
clang
clementine
cln
cloudprint-server-systemd
clucene
clutter-gst
cmake
cnetworkmanager
coin
colord-gtk
consolekit
cowsay
crypto++
cuda
cups
cups-filters
cups-pdf
cvs
dasher
dbus-sharp
dbus-sharp-glib
dee
devil
dhcp
discount
django
dkms
dmxproto
dnsmasq
dnssec-anchors
dnsutils
docky
dotconf
doxygen
draftsight
e_dbus
ecore
edje
eet
eeze
efreet
eigen3
eina-svn
eio
ekiga
electrum-git
elementary
embryo-svn
emotion
enlightenment17
eog
ethumb
evas
evas_generic_loaders
eventlog
exo
extremetuxracer
farstream
ffmpeg-compat
ffmpegthumbnailer
firefox-aurora
firefox-moonlight
fixesproto-ubuntu
flickrnet
fltk
foomatic-db
foomatic-db-engine
foomatic-filters
fortune-mod
fortune-mod-calvin
fortune-mod-chucknorris
fortune-mod-darkknight
fortune-mod-himym
fortune-mod-hitchhiker
fortune-mod-matrix
fortune-mod-montypython
fortune-mod-multidesk
fortune-mod-starwars
fortune-mod-tbbt
fortune-mod-twoandahalfmen
freecad
freecad-git
freeciv
ftgl
garcon
gc
gcc-fortran
gconf-sharp
gdata-sharp
ginac
gkeyfile-sharp
glpk
glproto
gmrun
gnokii
gnome-desktop2
gnome-disk-utility
gnome-do
gnome-do-plugins
gnome-font-viewer
gnome-games
gnome-games-extra-data
gnome-icon-theme-extras
gnome-js-common
gnome-keyring-sharp
gnome-media
gnome-mime-data
gnome-speech
gnome-system-log
gnome-vfs
gnome-video-effects
gnuplot
goocanvas1
google-breakpad-svn
google-earth
google-talkplugin
granite-bzr
graphicsmagick
graphviz
gsl
gst-libav
gst-plugins-bad
gst-plugins-good
gst-plugins-ugly
gtest
gtk-engine-equinox
gtk-engine-unico
gtk-qt-engine
gtk-sharp-2
gtk-theme-ambiance-blue
gtk-theme-slickness
gtk-vnc
gtk2-ubuntu
gtk2-xfce-engine
gtk3-ubuntu
gtk3-xfce-engine
gtkhtml4
gts
gucharmap
gudev-sharp
guile
gvfs-smb
hdf5
hedgewars
hostapd
hplip
hpoj
hsqldb-java
humanity-icon-theme
humanitycolors-icon-theme
hwloc
hyphen
ibus
ibus-qt
icedtea-web-java7
idnkit
imake
initscripts
inkscape
inotify-tools
iptraf-ng
ipython
ipython2
jdk7-openjdk
joystick
jre7-openjdk
jre7-openjdk-headless
kate-themes
kde-agent
kde-base-artwork
kdebase-katepart
kdebase-konsole
kdebase-kwrite
kdebase-lib
kdebase-workspace
kdeedu-analitza
kdeedu-kalgebra
kdepim-runtime
kdepimlibs
kdesdk-kate
kdesdk-okteta
kdeutils-kgpg
ld-lsb
ldns
lesstif
lib32-curl
lib32-flashplugin
lib32-google-breakpad-svn
lib32-json-glib
lib32-libappindicator
lib32-libdbusmenu
lib32-libdbusmenu-gtk2
lib32-libglapi
lib32-libindicator
lib32-libtxc_dxtn
lib32-libxvmc
lib32-nas
lib32-nvidia-utils
libbluray
libbonobo
libbonoboui
libburn
libchamplain
libcl
libdbusmenu
libdbusmenu-gtk2
libdiscid
libdmtx
libdmx
libedit
libftdi
libgdiplus
libgles
libgnome
libgnome-data
libgnome-desktop-sharp
libgnome-media-profiles
libgnomecanvas
libgnomeui
libgpod
libgsf
libieee1284
libindicator
libirman
libisofs
libkdeedu
libkgapi
libkolab
libkolabxml
liblastfm
liblinebreak
liblouis
libmediainfo
libmikmod
libmpd
libmtp
libmusicbrainz3
libmusicbrainz4
libmusicbrainz5
libmysqlclient
libowfat
libpng12
libpng14
libpst
libqalculate
libqxt
libreoffice-base
libreoffice-calc
libreoffice-common
libreoffice-draw
libreoffice-en-GB
libreoffice-gnome
libreoffice-impress
libreoffice-kde4
libreoffice-math
libreoffice-postgresql-connector
libreoffice-sdk
libreoffice-sdk-doc
libreoffice-writer
libspnav
libstatgrab
libtool
libtorrent
libunique3
libva-vdpau-driver
libvncserver
libwebp
libwpd
libwps
libx86
libxfce4ui
libxfce4util
libxfcegui4
libxfixes-ubuntu
libxml++
libxp
libxxf86dga
libyaml
libytnef
libzeitgeist
libzen
light-themes
lincity-ng
linuxdcpp
liquidwar
lirc-utils
llvm
locky-git
love
lpsolve
luajit
luarocks
lxappearance
lxc
lynx
mac-os-lion-cursors
mac-os-lion-icons
mac-os-lion-theme
mac4lin-gtk2-theme
mari0
mash
mediatomb
medit
mencoder
mercurial
metasploit
mlt-python-bindings
monaco-linux-font
mono
mono-addins
mono-upnp
mono-zeroconf
mplayer
muffin-wm
mutagen
mx
mysql
mysql-clients
nasm
net-snmp
netkit-bsd-finger
networkmanager-openconnect
networkmanager-vpnc
nginx
nmap
notify-sharp
nvclock
nvidia
nvidia-bl
nvidia-cg-toolkit
nvidia-utils
obexfs
obexftp
obextool
octave
octave-symbolic
omg-suite
opal
openbox
opencascade
opencl-headers
opencl-nvidia
openconnect
openmpi
openshot
openssh
opentracker
opentracker-open
orage
orbit2
osx-aluminium-icontheme
pacman-color
parallel
parcellite
pdcurses
perl-gd
perl-gdtextutil
perl-xml-libxml
perl-xml-namespacesupport
perl-xml-sax
perl-xml-sax-base
php
physfs
pivy-hg
pms
pngcrush
polkit-kde
poppler-qt
portaudio
postgresql-libs
preload
printproto
prison
ptlib
pycups
pygoocanvas
pyqt-common
pyrex
pysmbc
python-configobj
python-distribute
python-docs
python-m2crypto
python-pybluez
python-virtualenv
python2-apsw
python2-docs
python2-ecdsa
python2-httplib2
python2-netifaces
python2-pycurl
python2-pyqt
python2-reportlab
python2-sip
python2-slowaes
python2-south
q4wine
qbittorrent
qca-ossl
qdjango
qhull
qimageblitz
qpdf
qr-code-creator
qrencode
qt-doc
qtcreator
quodlibet
quodlibet-plugins
razor-qt
reflector
ristretto
rsvg2-sharp
rsync
rtorrent
ruby
ruby-msgpack
sandfox
sane
screen
sdl_gfx
sdl_mixer
sdl_net
seahorse
seed
serf
shared-color-targets
sip
smpeg
soqt
spandsp
sparsehash
speech-dispatcher
sqlheavy
sqlitebrowser
subversion
suitesparse
supertuxkart
swig1
syslog-ng
system-config-printer-common
systemd-ui-git
tablelist
taglib-sharp
tcllib
telepathy-farstream
telepathy-mission-control
texlive-bibtexextra
texlive-core
texlive-fontsextra
texlive-formatsextra
texlive-games
texlive-genericextra
texlive-htmlxml
texlive-humanities
texlive-latexextra
texlive-music
texlive-pictures
texlive-plainextra
texlive-pstricks
texlive-publishers
texlive-science
texmaker
thunar
thunar-archive-plugin
thunar-media-tags-plugin
thunar-volman
tk
totem
traceroute
transifex-client
translate-toolkit-git
tree
trojita
tsmuxer
ttf-ms-fonts
ttyqr-git
tumbler
ubuntu-mono
unace
unison
unvanquished
ussp-push
valgrind
varka-bzr
vbetool
vim
vim-runtime
vinagre
vpnc
w3cam
w3m
warmux
warmux-data
whois
winegame
wnck-sharp
wow-2-themes
wow-themes
wxcam
xaw3d
xbindkeys
xerces-c
xf86-input-acecad
xf86-input-aiptek
xf86-input-keyboard
xf86-input-mouse
xf86-input-vmmouse
xf86-input-void
xf86-video-apm
xf86-video-ark
xf86-video-ast
xf86-video-chips
xf86-video-cirrus
xf86-video-dummy
xf86-video-fbdev
xf86-video-glint
xf86-video-i128
xf86-video-i740
xf86-video-mach64
xf86-video-mga
xf86-video-neomagic
xf86-video-nv
xf86-video-r128
xf86-video-rendition
xf86-video-s3
xf86-video-s3virge
xf86-video-savage
xf86-video-siliconmotion
xf86-video-sis
xf86-video-sisusb
xf86-video-tdfx
xf86-video-trident
xf86-video-tseng
xf86-video-v4l
xf86-video-vesa
xf86-video-voodoo
xf86dgaproto
xfburn
xfce-theme-greybird-mac
xfce4-appfinder
xfce4-artwork
xfce4-axe-theme
xfce4-battery-plugin
xfce4-clipman-plugin
xfce4-cpufreq-plugin
xfce4-cpugraph-plugin
xfce4-datetime-plugin
xfce4-dict
xfce4-diskperf-plugin
xfce4-eyes-plugin
xfce4-fsguard-plugin
xfce4-genmon-plugin
xfce4-mailwatch-plugin
xfce4-mixer
xfce4-mount-plugin
xfce4-mpc-plugin
xfce4-netload-plugin
xfce4-notes-plugin
xfce4-notifyd
xfce4-panel
xfce4-power-manager
xfce4-quicklauncher-plugin
xfce4-screenshooter
xfce4-sensors-plugin
xfce4-session
xfce4-settings
xfce4-smartbookmark-plugin
xfce4-systemload-plugin
xfce4-taskmanager
xfce4-terminal
xfce4-time-out-plugin
xfce4-timer-plugin
xfce4-verve-plugin
xfce4-wavelan-plugin
xfce4-weather-plugin
xfce4-xkb-plugin
xfconf
xfdesktop
xfwm4
xfwm4-theme-prelude
xfwm4-themes
xinetd
xlockmore
xmlrpc-c
xmountains
xonotic
xonotic-data
xorg-appres
xorg-docs
xorg-fonts-100dpi
xorg-fonts-75dpi
xorg-smproxy
xorg-utils
xorg-x11perf
xorg-xcursorgen
xorg-xdpyinfo
xorg-xdriinfo
xorg-xev
xorg-xinit
xorg-xkbevd
xorg-xkbutils
xorg-xkill
xorg-xlsatoms
xorg-xlsclients
xorg-xpr
xorg-xprop
xorg-xvinfo
xorg-xwd
xorg-xwininfo
xorg-xwud
xpdf
xsane
xscreensaver
xsel
xulrunner
yasm
yelp-xsl
zenity
zqr