What are some things that you can buy that will always have value?

I know land, house, and gold, silver, and other commodities. Is there anything else that has value. Example, say I'm dead broke and I need some money to where I have to sell something I own in the future. What's valuable? Help me out on this one? Also, I've dedicated myself to spending less with my money, and when I do buy something. I only want to buy things that are going to be of value or at least I can get something out of it if I decide to let it go. I have sportcards, very old ones, however, I think I'd be a fool to sell those right now.