Install docky, gnome-do, gnome-shell and zeitgeist

# install gnome-do
sudo add-apt-repository ppa:do-core/ppa
sudo apt-get update
sudo apt-get install gnome-do

# install zeitgeist
sudo add-apt-repository ppa:zeitgeist/ppa
sudo apt-get update
sudo aptitude install zeitgeist

# install gnome-shell
sudo add-apt-repository ppa:ricotz/testing
sudo apt-get install gnome-shell
gnome-shell --replace

# Links
http://wiki.go-docky.com/index.php?title=List_of_helpers
https://addons.mozilla.org/de/thunderbird/addon/72199 - Docky Unread Count (Thunderbird extension)