Shelving units that fit perfectly into corners are a space-conserving way to store all kinds of items, and this is one of the cheapest and easiest ways to create your own. Buy a few magazine or file holders -- the ones that stand upright and hold about 12 magazines. Flip the holder sideways and fit it into a corner. Fasten each side of the holder to the wall with screws (washers help for extra stability). You’re done! A mini file folder shelf, perfect for holding everything from papers to technology to odds and ends. You can space 5-10 of these up one wall corner for a built-in shelf effect.