The Deathly Hallows Boxes
This idea started out as an engagement ring box and has become one of my most popular items. The original is made of purpleheart with a copper wire inlay. I've since transitioned to an epoxy and crushed stone inlay which looks very nice and uniform. The engagement ring boxes are held together with 3 pairs of magnets and can easily be opened by twisting the top off.
Recently I scaled the design to a small jewelry box for my niece. She's a huge Harry Potter fan so I thought this would be a great gift. This design has the same epoxy and crushed stone inlay but instead of magnets, it has high quality Brusso hinges holding it together. Videos of both styles are shown below.