I live in a 1950's building with the original windows. When the tempurature dips below minus 25 my windows frost up and I pretty much know it's too damned cold. I took a closeup of the frost then cropped a portion out of that. Some fun with Topaz Detail and we have ourselves ...ummm something ..
http://farm3.static.flickr.com/2579/...faab65e0_o.jpg