Turn an old Altoid tin box to a portable Yatzee case with room for five dice, a small pen and a folded sheet of paper.

It is modeled to fit 16 mm dice and a 98 mm long Zebra Compact F301 pen (with a diameter of 10 mm).

It is a snug fit, so in order for it to fit despite the thickness of the folded lip on the edge of the tin box, I have made the insert into two parts. No glue is needed. It should snap in place.

There is a thin wall (between dice one and two in the image) that you can just break off in case these two dice are too tight.