Baleen

Used by whales to catch food. Whale swims near the surface and foot is
caught and tapped by the baleen. It does not collect frost so Alaskan
Natives used it for such things as fishing line and snares. Baleen
hairs were used as bow strings and woven into fish weirs, even into
mats. Today they may make letter openers, boats, toys, and inscribed
plates are made for the tourist market.