Extreme Window Frost

What is there to do on a cold winter afternoon?  I did something I haven't done in years.  Took pictures of window frost.  The last time I did it was when I used a film camera.  All of our downstairs windows have been replaced since that time and so there is no window frost.  We do still have some older windows upstairs.  With the cold weather we have had this winter I was able to think again about doing some shots.  And now digital is great as you can see immediate  results and make changes as needed to get the picture.  Lenses have also improved.  I have a 1:1 close-up lens.  I used some of my older close-up filters with this to get an even closer look and it was pretty easy.