Interesting you would bring this up - as at the encouragement of my better half i threw out a whole bunch of the flattened boxes last week (fire hazard you know) - peace has now returned to the valley.
Someday, I'm going to build a large box-style coffee table with a hinged-framed glass top so that I can lift it up, and put my sentimental-favorite Boxes and Play Sets inside just to look at and admire and daydream of "my childhood happy memories." I still get that "Wow!" feeling whenever I pull them out; just like the first time I discovered them in the hobby shops.
The first boxed sets will be my 1960's-1970's Airfix Fort Sahara Boxes (with contents) - The first "Comic Book" style artwork and the last Blue-Box very realistic-like. In fact I like both of the same style Fort Apache sets too.
In those days, the artwork inspired me to beg/borrow/steal/or somehow buy the Play Sets, even if I had to find enough Coke bottles discarded in the tall, grassy, fields surrounding my subdivision to turn in for coin deposits at the local supermarket.
Yes, these magical boxes I'll keep and I'll take to the grave with me.
Chris and other Forum Members - Which are your "Cherished, Favorite, Boxes?"
Thanks for asking and - Happier & Happier Collecting!