What uses do humans have for echinoderms?

Aside from cuisine, humans have other uses for echinoderms.  Sand dollar and sea urchin skeletons and dried starfish have long been used as collectible souvenirs.  In addition, there are medical uses for echinoderms, particularly pertaining to research of the toxins of some sea cucumbers, which have shown promise in hindering the growth of tumors.  Farmers in areas of the world where limestone is scarce also use the crushed calcareous tests or shells of echinoderms in order to lime their fields.