A lot of notebooks.
I buy them on sale whenever I notice them. Some are scribbled on every single page. Some are half-filled. Some have a single page or two of writing before they were forgotten. I love finding these notebooks and looking through them. Ideas and plotting for old books, discarded chapters or POVs, so on and so forth.
But every time I look through an old one, I have this secret, desperate hope: I want to find an idea. I want to rediscover something I thought of on a whim and then left behind. I want to see it and think OH MY GOSH THERE IT IS. THE IDEA. THE GENIUS IDEA I'VE BEEN CHASING THIS WHOLE TIME.
Of course, this is what I find instead:
I have no response to that.
Inevitably, Present-Me ends up annoyed with Past-Me for writing nonsense, or a handful of unrelated key words that probably made sense at the time. (Oh, who am I kidding, they definitely didn't even make sense at the time, much less months or years later.)
But Present-Me can't grudge Past-Me her slightly malicious glee at being so unhelpful, because Present-Me has the same twisted sense of humor and appreciates the joke Past-Me is always playing on her by being so maddeningly odd.
Future-Me, however, wishes Present-Me and Past-Me would quit leaving her all the really hard work.