I show a range of different industrial components that you can salvage from thrown out machines. Main breaker panels, x-ray and UPS systems. Look at privately owned scrap yards and metal recyclers in your area to get the same opportunities to find stuff like this. You have to be prepared to pay per kg for some of the stuff that contains large copper pieces like the big contactors or transformer scrap price for the filters. Overall it is still a very cheap way to obtain expensive parts.