Envision your place in the universe

For the beginning, I'd like to make you realize, how small we actually are. The vastness of our universe is almost impossible to comprehend for a human's mind. 
The Milky Way, our home galaxy, consists of an estimated number of around 400 billion stars alone. Now imagine many of them having planets (estimations are ~ 50 billion) - and those having moons! And that's just our galaxy, there are billions of other ones, in some way it can be seen as an infinite number. How many life forms, how many civilizations might evolve in such an endless sea that forms the space above our heads?
This graphic is a scale comparison of our sun to the planets of the solar system, amended by some interesting facts. 1.3 million Earths fit into our Sun! Which is a yellow dwarf star - there are way bigger stars out there in space.

Click the image for full resolution!
Source: http://waynedorrington.blogspot.com/2011/02/infographic-no2-sun.html

And this video shows you how size is all relative - making our Earth and the sun look like tiny mites!

(You can watch it in HD by clicking the video to open the YouTube page.)