We're gonna start out short and sweet; no need to jump into the deep end and freak ourselves out. Here's a few short videos to tickle your thought bone and provide a nice warm up to the issues.
I particularly love this first one. After watching it ask yourself if you think you, or anyone you know, has ever successfully comprehended the actual size of our KNOWN universe? Then consider the implications of that. :) Cheers!
A playlist of 14 short videos.