I've misplaced at least 4-5 books that way, so believe me, I feel you.
But the worst was when I accidentally dropped my wallet inside a "not-completely-full" shortbox, which I then closed and moved into deep storage. Later that day, when I realized I didn't have my wallet on me, I immediately thought I had lost it in the street somewhere. So I said goodbye to about 350 euros, cancelled my credit cards, issued a new I.D. card, new driver's license, etc...
Found the wallet 4 years later, when I had reason to open up the Marvel 2099 shortbox again.
Well that's a nice surprise, to find money you thought you lost (thumbs u