My answer to this question is: It's worth 0. zero. zilch. bupkis. nada. You get the picture.
The reason for this valuation is simple: It pays no dividend. It hasn't shown any signs of ever paying a dividend again. (It used to, up till 95' or so). The future dividend stream is fairly easy to evaluate, using any factor of present value - when the future payments are zero, zero, zero and zero again. It doesn't take a mathematician to work that one out.
Of course, the company does generate a lot of cash, and sits on a nice little ten billion mound of greenback. But absent the commitment to return that cash to shareholders, one has to prudently assume that it will all be wasted on buybacks (to compensate for all-too-generous option plans), acquisitions at premiums most outrageous, and general mismanagement. How much of it, if any at all, will ever end up in the hands of shareholders, is anyone's guess. And guesswork is not the best foundation for investment.