I bought a piece of 1.5 inch stiff foam to try to fix a sag in a bed. It didn’t work but having that thick piece of solid foam around has been a life saver.
Need something flat to put a laptop on? Throw it on the foam. Going to be doing something that requires you to be on your knees for a while? Get the foam!
It went from stupid purchase to something I’d gladly replace if it broke.
Workbenches with butcher block table tops and metal legs for my home office. I was a life long user of cheap metal and glass top desks that you get from Walmart, Staples, etc. These things cost a lot more, but they are worth every penny. And unlike the cheaper stuff, will last years and years unless the house burns down.