I looked at my insane pile of notebooks a while back, and decided to just throw the damn pile in the trash. But then some great people at Micro.blog convinced me to keep parts of it.
So, I went through them all and decided to keep everything that contained stuff I have written. But I decided to get rid of everything that was lists, tasks, notes etc. The result was that most of it are gone. I think the result was that 2⁄3 of my notebooks are gone. And most of the new ones I fill up are thrown out as soon as I am done with them.
This have done a lot to make my netbook collection more manageable, and limited to what might be interesting at some point.