I like this video from Matthew McConaughey:
This is Why You're Not Happy.
It dovetails with a book I just read about several leaders, amongst them Peter Drucker, who advised people to decide what they want to be great in as well as deciding what they would abandon & choose
NOT to become great in (distractions, time-wasters, etc.)
http://youtu.be/p0p1fjLPjYQ