>> right.  i didn't mean that things that were reflectively symmetric
>> were not okay, but just that that wasn't the operating principle.
>
>I would think that rotational symmetry is not necessary at all. What I
>guess would be necessary for stable operation is that, given a line at
>any angle passing through the centre of the disc, the centrifugal force
>exerted by the masses on either side of that line would be equal.

that is, of course, the more technically correct answer, but whereas
most people will unwittingly put cute things in their cd drives, i
think a lot of people would actually balk at putting in some
intricately carved cd remnant simply because it preserved some arcane
rule of engineering.

personally, i'd find it quite amusing.

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