[mikecoles]

Unsure about the entire US... For my area they were called "window fans" in previous times. Before air conditioning was prevalent, you'd use these box fans, placed in the window, to circulate air to provide a more comfortable environment.

In years past, the fans were beefier than the current generation. They also used metal fins. Speaking into one made a vaguely similar effect to speaking Like Darth Vader. It was entertaining as a child.