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.
Agreed! Just beware that the Amazon Basics ones used to be awesome (black or grey ones) but the new ones (green) are garbage. I have some of the older ones that are 8 years old and still going strong, where as the new ones wouldn't hold a charge after about a year of use.
I recently bought some Panasonic eneloop ones and although they are more expensive they seem to be much higher quality.