It's difficult to imagine something so much bigger than our Sun isn't it. Astronomy is such an interesting subject, they should really push it more at school/college so more people get into it at an earlier stage and it could replace some of the crap you get tought at the moment in schools.
I love simple demonstrations of perspective like that, and yes you can go quite mad pondering these things!I became fascinated with this subject as a young child and still remain so - it's a never ending think hole