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When it comes to getting the longitude and latitude of specific locations, I am a junky. Weird, I know, but I use it often. I actually have a bookmarklet to grab the lat/long from the old Google Maps.
But with the new Google Maps, it is no longer needed or supported.
All you need to do is click anywhere on the map and Google will give you the coordinates, the longitude and latitude of where you clicked.
For me, it comes in handy when testing formulas for sunrise/sunset and other time related offsets based on location. Not sure how it is helpful for others but I use it all the time.
Forum discussion at Google+.
