We had a recent post about jars so lets start with jar lids. Mason jars have two types of lids. You have the general metal screw on lid as well as a variation of that - the two part lid. When you buy these lids and have to replace them, you can just buy the centre piece, which saves buying more metal. The centre disc holds the rubber which makes the jar air tight. It is that part that will wear out, and therefore need replacing. See below.
There are different types of lids that can be used on glass jars. The green lids below are the Fowlers Vacola lids that you can buy to fit on your preserving jars when you open them. It's not a good idea to keep the metal lid on the jar when it's open. But you don't need to buy the FV lids. The red lid below is in a Fowlers jar but it's actually the stopper from a French mustard pot - recycled from my son's restaurant. If you find any of these tops, or anything similar, grab it and add it to your cork and lid collection. Also below is a pottery lid, originally from a sugar container that broke, I now use it for my FV jars. Anything safe and solid is good. It will be safe if it has been sold to cover some kind of food, and solid if it's glass or pottery with no cracks. Also below is an old lolly jar, it's on the far right. It is partly glass, partly plastic. anything like this is great and if you save these tops, at some point you'll find a jar it will fit. Often things don't have to be air tight, they just need to be covered so the contents of the jar aren't open to the air. For instance, the FV green tops fit fairly loosely, so does the red top, but that's fine.
Cloth covers can also be made from a clean tea towel or any clean cloth you have at home. You can use a cloth cover instead of plastic wrap to cover cheese that is stored in the fridge. If you do this, simply wet the cloth, wring it out well so that it's just slightly damp and cover your cheese with that. Moisten it again when it dries out. This is a very old way of covering cheese but it still works well.
Our last photo is a dish stack that can be used to store two different types of foods. I generally place my stack on a larger plate at the bottom. On top of that is a bowl that could hold something like salad. The bread and butter or salad plate on top of that covers the salad and also holds leftover salmon cakes or cheese (or whatever) and this is covered by an upturned bowl. It saves space in the fridge and also covers your food without using plastic.
I hope this has given you a few ideas to use in your kitchen. Many things we commonly throw away can be reused, you just have to think outside the square. So if you've started a jar collection, or already have one, also think of how you will cover your jars, and start searching.