Mechanical things. Vintage farm machinery - tractors, hit-n-miss engines. throttle-governed engines, tools, etc... Vintage motorcycles, cars boats saws guns... Things that you could work on without it falling to pieces on you. Old household things, furniture, even old kitchen stuff.
Stuff that, like was said, was built with a purpose and for me, built by people that took pride and a sense of ownership in what they made. That what they made, what they crafted, was a statement of who they were and how they conducted themselves in life. A code of craftsmanship and accountability that for the most part has been long since abandoned and forgotten.
I've worked in the building trades off and on for over 30 years and jeez just look at the difference in quality between a house built by returning WWII Veterans and the literal crap houses that are being shat out today.
Wife is a semi-retired Chef, same thing in her trade. The tools and equipment that they use the difference in quality in design and craftsmanship between 75 years ago and today are night and day. It's all throw-away junk today.
Heck, beer fridge in the garage is an old Kelvinator made by American Motors and it runs at 30 degrees day in and day out for how many years? Yet we can't keep a fridge in the kitchen for more than 5 today. When one of her old Garland 6 burner stoves weighs double what a new 10 burner weighs, it just make you shake your head...
Sorry for the rant. I like old mechanical stuff, lol