This one, by two Russian daredevils named Vitaliy Raskalov and Vadim Makhorov, might be the scariest yet.
Posted on Reddit by user Vintage_Milk (and first found via Daily Picks and Flicks), the video shows the teens climbing the second tallest building in the world: the Shanghai Tower in China, which is still under construction and will stand at over 2,000 feet tall.
The truly dizzying heights start around the 3-minute mark, and then get terrifying at 4 minutes.