I LOVE this post by Here We Are. Now What? called Impossible Things. Terry discusses the how impossible goals can help you and I achieve more.
"Impossible Goals address things that need to be accomplished, but which appear to be out-of-reach for one reason or another. There seem to be too many insurmountable barriers."
I whole-heartedly believe in shooting very high. Sometimes we reach the stars and other times we get higher than we would have with wimpy goals. And there is a way to create inspiring big goals without becoming deflated when they are not achieved. It is important to see big goals for the magic that they are.