http://skysurvey.org/
and how it all came into being -
the story. worth a read.
the guy quit his job and took 37440 exposures with 6 synced cameras (no telescope) in north america and africa. then stiched them together.
et voila: the most beautiful night sky navi app I've seen, so far.
I love it because I love the story behind it.
check it out