Check it out.
1. Easy to make. Square cuts on everything but the X-shaped side supports, and those are only a 60-degree angle, easy to create with a protractor if you don't have a saw that tilts just the right way already.
2. Inexpensive as you like. I've seen whiteboard for $2 to $10 depending on dimensions. You could also probably do this by adapting those shipping pallets, but make sure you get the untreated or heat-treated ones instead of the chemical-treated ones, if you're going to use this for soap or food storage. Of course, you could also use really fancy wood, sanded smooth and maybe painted/carved/woodburned decoratively, and make this a showpiece in a workroom in which you do get visitors. Difference between garage/basement storage, versus something you keep within your actual living space.
3. Very shallow shelves, so you're stacking seven shelves worth of soap bars with little space between them, instead of two or three layers like you'd do with a normal book shelf or the like.
4. This will work for food storage, soap drying/storage, air-drying your laundry (sand the wood carefully if you want to dry your delicates this way), school or office supplies (especially if you make the shelves solid instead of separated slats), tools (again, use solid shelf-bottoms), extra guest plates and flatware, table linens, or flat-storing posters or documents of any kind. Or pretty much anything else that isn't overly tall, really. Just adjust the dimensions if your posters (or whatever) are larger than the inner dimensions of these shelves.
5. If you can make one of these, you can absolutely make your own soap molds too, which will also lighten your financial load in making soap. (By the way, I did that once. Yes, I'm overly proud of it. Yes, I fully expect you to pretend to be JUST AMAZED at how AWESOMELY AWESOME it is. If you're not, just hush, nobody asked you.

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