Whenever the The Electornic Frontier Foundation (EFF) commends Ubuntu for "retrofitting operating systems to support privacy against local attackers" as a worthy objective, I'm inclined to sit up and take notice. Since Ubuntu Precise Pangolin (12.04) these privacy setting have been integrated out of the box as a feature in the System Settings menu. It's called Activity Log Manager (previously Zeitgeist Global Privacy), a GUI frontend to partially control Zeitgeist. It's what powers Ubuntu's Dash in the Unity desktop. Here's how to use it to control what the Gnome activity log is recording.