I bought a minidisc stereo
back in the day. I was so proud of it. It's packed away and I can't bring myself to get rid of it. Partly because I loved it but also because it might be collectable one day and worth a mint (probably not.)
Have you held onto anything from your past that you just can't get rid of in the hope it might be valuable one day.
Random things, not jewellery that you already know is valuable.