I definitely think this is a fun thing to do either at Christmas time, or even now, after the holidays are over... to keep a little magic in the air. It's a fun middle of the winter type of idea. You could even have your children help you build it if you are stuck indoors one cold day.
A friend of mine also did this on her childrens' bedroom doors instead because she didn't have a white fridge, so do whatever works.
Here are some easy ways to make this snowman, just cut these shapes out of construction paper.
Then I put it all away like this, after carefully taking it off the fridge, in hopes that my husband doesn't have to recreate it next year.