craftgrrl | Olive shells and nothing to craft!

I'm crashing with a cousin this fall and I want to come up with a gift for the host. He's terribly creative so the pressure's on! He's got a bit of a thing for olives (he moved to an Olive Street when he bought his first place) so I was thinking of playing on that. I know he's got a lot of olive paraphernalia but I'm from the coast and over the years have collected several olive shells, which I think could be a fun spin.

But I have no ideas...Jewelry would be easy, but it's for a guy. I've hit a wall! No ideas!

Need help...anyone seen anyone do cool things with shells, or small oblong objects?

Olive shell courtesy of Wikipedia