This one made an impression on me

"Don't waste all your time sitting at home on the computer.
Go out, enjoy social life and friends. You can always learn programming, but acquiring social skills is much easier when young."

http://www.quora.com/Self-Improvement/If-you-could-go-back-in-time-and-give-your-10-year-old-self-life-changing-advice-what-would-it-be