title: Cron with notify-send
body: <p>I need to show a notification from a cron job. My crontab is something like:</p>
  
  <pre><code>$ crontab -l
  # m h  dom mon dow   command
    * *   *   *   *    Display=:0.0 /usr/bin/notify-send Hey "How are you"
  </code></pre>
  
  <p>I checked <code>/var/log/syslog</code> and the command is actually executed every minute but it doesn't pop up the notification.
  Can anybody help me understand why?</p>