This was exactly what I had in mind.....the old twin beds and turning the bed posts! I've got a set of two walnut twin beds in the basement storage that my wife won't let me destroy, yet we've had no use for for 15 years!
I feel your pain. I suspect a lot of us do. I've been been storing old crap that belonged to previous generations for many years.
I like old stuff, and I suspect of lot of us do. But, chances are our belongings will be a burden on our kids. There's been a major cultural shift, and the younger folks just don't want "brown" furniture anymore.
I suspect this is a result of widespread affluence. When all of your possessions can fit in one steamer trunk, your stuff is valuable to your kids. But, if you have a house filled to the brim with stuff, it's tough to be sentimental about it.
So, if you can reclaim lumber from old furniture without cause marital problems, go for it and without guilt. With the caveats others here already posted.