Besides boiling, good way to clean ocean driftwood?

I'd recommend using boiling water, in order to kill anything that could be living or possibly might come alive (ex; eggs from any snails, bugs that have nested within, and even terminates if the wood has been left out for so long without any water touching it).

You could also dip it within white vinegar for a day to make sure anything on the outside is cleaned up (or the vinegar that soaks within the wood, is treated).

You can soak it in peroxide. You will want to let it soak for 2 to 3 days and then let it soak another few days in water to remove any buildup or dead parasites and other items.