Victorinox Swiss Army Knife. It's still kicking. The amount of times I've used it, it saves so much time than looking for the proper dedicated tool.
A metal wallet. Definitely worth it if you don't carry a lot. Mine is maybe 10 years old now or more.
3+ year old used Lenovo Thinkpads, these things are great if you need a budget laptop that's not for gaming. A lot of companies lease them. When the lease expires you can get them very cheap because they flood the market.
General Military Surplus. We have a shop a few kilometers a way that sells surplus. They get in brand new stuff all the time. Still in packaging. It's built well. Keep in mind military surplus isn't just in the field stuff. Laptop bags, shirts, blankets, hats.
A pet. Worth every penny. Got my cat from a shelter, he's been there for me through thick and thin. Gives great hugs.