It is often said that there are more stars in the Universe than all the grains of sand on all the Earth's beaches. That just blows my mind. Click Here for the math explaining this concept. Along the same line of thought comes a quote from one of my favorite movies.
You know, there are four hundred billion stars out there, just in our galaxy alone. If only one out of a million of those had planets, and just one out of a million of those had life, and just one out of a million of those had intelligent life; there would be literally millions of civilizations out there. (From the movie Contact, 1997)
Possibly something to think about when walking along the beach.
As always, comments are appreciated