The other thing we did with pallets was to build an extremely temporary "dock" to launch our 11' aluminum boat. Our shoreline is quite muddy due to the clay and low water. We stacked a couple pallets at the water's edge so that we could more easily get in/out of the boat. That worked nicely.
Then, since we hope the water will get higher, we stacked eight pallets flat, end-to-end and up the slope, to build a eight-pallet-long dock. We looped them together with wire and staked the whole thing down. For a while, it will aid our boat launching. Once the water comes up, it'll be spawning structure for a while. Eventually, it may be deep structure.
