alt Hacker NewsAgreed on jars. We use Weck and Ball for different purposes, and truly love them. It's odd to be so attached to trivial chunks of silicon, and we're not attached to them as individuals but I appreciate them every single day.
I struggle with discarding the original packaging. Sometimes I want to know what the nutritional content of product X is. I have a guilt drawer of collapsed packaging. This has the added benefits of confirming formulation changes, shrinkflation evidence, and remembering brands of certain commodities that were better or worse than others. It also satisfies my "preserve all available data" instincts, which I imagine many other geeks share -- although it is only tolerated with amusement by other members of my household.
I take a photo of almost any package. I have a folder with labels from years ago. I admit that if the manufacturers of X change the ingredients without changing the design/layout, I wouldn't notice. So I might have to set up a system where I remind myself to check everything once every few months to compare it to the photos I have. But at least the photos don't take up any space. I used to have a drawer with packaging and receipts, too, but it was unmanagable.
For jars I use regular jars for most things. Regular jars of food you'd buy in the supermarket. They're basically free. I just have to soak them and remove the original label. For some things I like tall jars, the kind tomato sauce comes in. Doesn't really matter, except they fill certain shelves of a specific height better.