Pallets are an inexpensive, often free resource you can use for a number of furniture solutions. Building shelf units out of pallets is easy, provided you find two pallets of the same design. Mismatched pallets will often have uneven gaps, resulting in shelves that are off level. Set aside an afternoon for this project from start to finish.
Sand all exterior faces of the pallet. Most pallets are made with unfinished wood, so splinters are a hazard if you don't sand.
Paint all exterior faces of the pallet, using a paintbrush, and allow to dry. If necessary, apply a second coat of paint.
Run a stud finder along the wall. Screw one pallet to the stud with two wood screws, the pallet set perpendicular to your floor. Mount the pallet so the gaps between its boards are horizontal.
Run the stud finder along the wall 32 inches from the first pallet. Mount your second pallet to that stud in the same way you did the first.
Slide a plank between the gaps in the boards of your pallets. You can arrange your boards in whatever pattern you like.
This design leaves a lot of pallet sticking out compared to the boards you're using. If you're ambitious, you can shorten the pallets or use longer boards.