Google Street Views on Google Maps can be a fun tool to play with, and yes, it is also useful. Yesterday, the Google Maps team posted on their Google+ page that they captured many of the balloons waiting to take off while sitting on 81st street in Manhattan.
You can see them yourself on Google Maps over here or here is a screen capture of what you would see on Google Maps:
It is pretty neat, don't you think?
Forum discussion at Google+.