A MS divulga há um certo tempo uma campanha publicitária que mostra que o Win2003 é até 10x mais barato que uma instalação Linux.

O CONAR da Inglaterra tá proibindo a propaganda por lá. Motivo: saca só um trecho do artigo da InternetNews:

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But, after being advised by IT experts, the ASA concluded that the ad, created by ad agency McCann Erickson, implied that the comparison was between Linux and Windows operating systems only. It would have made sense, therefore, to run the two operating systems on the same hardware. But Microsoft ran Linux on IBM's zSeries, which is more expensive and under-performs the rest of its line, while it chose the cheaper, faster Intel boxes for its own software.
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