I'm a big fan of Hugh MacLeod at gapingvoid.com. If anyone's found the balance between romanticism and realism, it's this guy. He's got a lot of great thoughts about dreaming big and making those dreams come true.
His most recent post is pure genius: Don't just sit there and dream big dreams and make big plans and work out every detail, do something about it! There is something you were put on this earth to give to the world. Figure out what that is and make it happen!