Powers of 10 (http://www.youtube.com/watch?v=s1jd8AgjP9k&eurl=http%3A%2F%2Fvideo%2Egoogle%2Ecom%2Fvideosearch%3Fhl%3Den%26q%3Dpowers%2Bof%2Bten%26um%3D1%26sa%3DN%26tab%3Dwv)
the scale of some stuff in the universe (http://www.youtube.com/watch?v=7J82yKdF5Mw&eurl=http%3A%2F%2Fwww%2Efilecabi%2Enet%2Fforum%2Fshowthread%2Ephp%3Fp%3D172594)
Relative sizes of the planets in our solar system (http://www.dailycognition.com/index.php/2007/08/16/picture-showing-size-comparison-between-planets-in-our-solar-system.html)