They scrape off algae and small animals off rocky surfaces using their wonder toothed tongue. Chitons have teeth coated by magnetite, making their teeth comparable in hardness to a kitchen kife!
David Macey, a scientist from Murdoch University said this about chiton's teeth in an interview with ABC Television: "Their hardness on a scale of 0-10 is 6.5. .. And a kitchen knife would be around about 6.3 , 6.4 depending on how good your kitchen knife was. So they are really are very hard, they could eat steel if they wanted to." Aren't you impressed!