Humans only tend to use 10% of their brains power right? Imagine befriending your subconcious and allowing it to use more. Hence more intelligence, concentration, memory and creativity. Also, with your subconcious as your friend you could ask it for favours such as... lucid dreams! With your subconcious as a close friend, you could communicate with it to help without opening your mouth. You could boost your life expectancy by fighting disease with that excess brain power... if you ask me, becoming friends with your subconcious may just be one of the best desicions in anyone's life. One question. How?
Edit: With your subconcious as a friend, you could tinker with that internal clock inside your brain, making time appear to slow down, for enhanced concentration and maneuverability. This is done by making the brain take in more information, therefore more detail and a slowed time perspective. Or, if you are bored out of your skull, you could make your brain take in less, making time go faster from your perspective.