It's summer, and if you live anywhere the sun shines, science dictates that it gets stupid hot inside your car when it's closed up and baking in the sun. According to this Japanese video, rolling down one window and opening and closing the opposite door a handful of times will quickly and effectively cool down a hot car.
The video's only two and a half minutes, but unless you understand Japanese (or can read the Chinese subtitles), jump straight to the 1:52 mark to get the picture. Reddit user binarysolo offers this loose translation:
Roll down a window on a side of the car. Let's go with the driver's side window. Go to the opposite side door (in this case, passenger side) and open/close it ~5 times. Just do this normally.
Source: lifehacker
