Some of his biggest ideas: - passion is not something we discover but something we earn or build over a long period of time. - Choose one thing that interests you (even if its a 'silly' interest) and has the potential to become a rare and valuable skill about which you could one day be passionate. - Pursue that through undergrad and after, until you really have a rare and valuable skill. - Leverage that skill to live a remarkable life.
His most recent post might be especially relevant: http://calnewport.com/blog/2010/10/16/the-passion-trap-how-t.... I have been writing about similar ideas at http://joshrule.com/blog/category/passion.
Again, you aren't alone. These feelings are common even in many people who generally know exactly what they want in life. The important thing is to learn how to deal with them and keep them to a minimum. Cal's blog provides some great steps toward doing that.