This interesting shape makes for a unique 6 sided die.
It has a convex hull that's a triangle dipyramid, an isohedron. Since a triangle dipyramid doesn't have parallel opposite sides, I started from a wireframe. Then I created a shape inside it that has sides parallel to the outside shape.
For more information on unique dice shapes, see http://loki3.com/poly/fair-dice.html.
2.728 w x
2.728 d x
1.074 w x
1.074 d x