I always think everyone knows about this stuff, but since I got to introduce an officemate to it this morning, I figured I'd link it here as well:
Click to view
The YouTube Channel - there are a bunch more of these, including the phenomenal A Still More Glorious Dawn Awaits, featuring Carl Sagan and Stephen Hawking.
I swear, this stuff makes me feel the same way Star Trek does - hopeful and full of wonder at the universe and the capacity of humans to do amazing things. It's like space church. Without any of the religion getting in the way.