He sounds very masculine-oriented so why not suggest learning to make some symbolic pendants that protect the warrior in him (chain mail made me think of armor)? Necklaces and bracelets that hold meaning are very popular among young people today. Maybe with a bead with a Japanese symbol for courage, bravery, strength, wisdom or something like that. His friends will want him to make them one.
Also, if he is older, you might suggest that he learn seed beading to give as gifts to female family members or girl friends.