From: Jacob Fugal <lukfugl@...>
Date: 2006-01-10T01:04:52+09:00
Subject: Re: [QUIZ] Dice Roller (#61)

On 1/7/06, Ron M <rm_rails@cheapcomplexdevices.com> wrote:
> Austin Ziegler wrote:
> > Novelty dice created in the past include:
> >
> >   d30, d100
> >
> > The latter is quite unwieldy.
> >
> > Strictly speaking, it is not possible to make a die (polyhedron) with an
> > odd number of faces,
>
> Uh, of course you can make such a polyhedron.  Consider the
> Egyptian and Mayan pyramids as examples of 5-sided polyhedron
> (four triangles on the sides and a square on the bottom).
> Adjusting the steepness of the sides can make it as fair
> or unfair as you'd want.
>
> Sure, they're not regular polyhedra, but neither is the d30 you spoke of.

In fact, I've seen a variation on this for the infamous "d3" somtimes
used in D&D. The standard approach is to roll a d6 then divide the
result by two (rounding up). However, one dice seller instead offers a
non-regular tetrahedron where one vertex is stretched out away from
the fourth side. This makes the three stretched side much more likely
than the fourth side, and given the dynamics of the dice, it is very
unlikely for it to land standing on that fourth side. So you have, in
effect, a three sided die. If the fourth side does ever come up, you
just reroll.

Jacob Fugal