Ubuntu operating systems with Unity can be enhanced to feature power commands straight into the Dash, and the installation is quite simple.
There are a lot of power users out there who are using the Dash the way it was designed, by writing everything that they need and executing the command. The Dash is also very useful if you have Scopes enabled.
That being said, I found myself searching for reboot or shutdown in Dash, only as a reflex, instantly remembering that there aren't any available commands for those particular functions.
Fortunately, the developers from Atareao Team have come up with an ingenious solution for this problem. All you have to do is install a PPA and voilà! You will get power commands inside the Dash.
The installation of the PPA is simple. All you need to do is open a terminal and enter the following commands (you will need to be root in order to make it work):
sudo add-apt-repository ppa:atareao/atareao
sudo apt-get update s
sudo apt-get install power-commands
The installation should only take a second. When it's ready, just look for shutdown, log out, restart, hibernate, and lock inside the Dash and hit enter if you want to execute any of the commands.