An interesting side of bedbug treatments:

The other day I took some books out of my freezer where they'd been for over four days at below zero temps, and I put them on my bookshelf.

As I then sat at my table, I could see what looked like heavy steam roll off the books and down the shelf and down towards the floor, though the steam disappeared after about a foot or so.

It must have been something like evaporation or waves of cold, but heavy.