Winter frost...

Frost grows on the window glass, 

forming whorl patterns of lovely translucent geometry.

Breathe on the glass, and you give frost more ammunition.

Now it can build castles and cities 

and whole ice continents with your breath's vapor.

In a few blinks you can almost see the winter fairies moving in...

But first, you hear the crackle of their wings.  

Vera Nazarian, The Perpetual Calendar of Inspiration