My rejection slips.
I'm moving, and at the same time, I'm getting rid of a lot of stuff. I no longer feel the need to keep physical copies of old rejection slips. I have about 540 altogether (a ream plus a novelette of paper!) Here's a pile of them. I'm keeping exactly one, which I'll share about later in the week. You can see, in this picture, that I submit to mainstream as well as genre markets, though not necessarily the same stories. I have NO idea what I sent to Redbook though, or when I sent it. Don't recall that one at all.