I installed the cheap and cheerful winter window films today and was astounded at the amount of air coming through my new windows. Granted, it is blowing 20-30 right now but I am thinking I might do both indoor and outdoor storms after watching the films move with the gusts. I have read Gary's inside storm ideas. Given that I haven't done the finish trim in the house yet, it looks like I can incorporate them pretty cheaply and relatively aesthetically pleasing in the process. Has anyone done both interior and exterior storms?