http://i14.photobucket.com/albums/a332/ ... erfrig.jpg
When I was stationed in Sioux Lookout, Canada, 47 years ago, we would open the windows and put bottles of beer on the sills. Shut the windows and wait a couple of minutes, at 30-40 degrees below zero it did not take long to get cold. Coldest I ever saw was 52 degrees below zero, that's actual temp, not wind chill factor. Brr.