I would argue that Microsoft has, contrary to attempts to claim the contrary, benefited from "computer piracy" in a big way.
Illegal copying of Microsoft software does not substantially reduce their revenues.
Reports suggest that there are tens of billions of dollars "lost" as a result of illegal software copying; reality is that if people acted in a legal fashion, buying the software that they use, they would only have bought a fraction of that $20B worth of software.
Illegal copying of Microsoft software reduces sales of other companys' equivalent software packages, thus increasing Microsoft's market share.
If Microsoft doesn't get a sale, at least nobody else got the sale either...
Illegal copying of Microsoft software results in increased dependence on their software.
I would further suggest that the computer book industry substantially supports illegal copying of software. If, for instance, you had bought Quicken, you would get their reasonably well-written documentation; the only real reason to need to buy the "Complete QUE Guide to Quicken" is if you copied it illegally.
Microsoft has taken this a step further; it doesn't matter if you buy the development tools; you can't possibly figure out how to use them unless you buy additional "documentation" from Microsoft Press. Even if you "stole" the software, you'll be going to them for documentation...
Furthermore, the use of the term "piracy" seems to me to be an abuse of the word "piracy."
The The Microsoft-English Dictionary describes the seemingly relevant term "Heroin Economics," described as a
Common practice of drug dealers looking to establish a customer base by providing free samples to "hook" users, at which time the dealer raises his prices for his product. Since people are now dependent, they will naturally pay whatever is necessary to obtain the substance. In the software world, for years Microsoft tolerated software piracy (both casual and organized) as its user base expanded and the company became a monopoly on the desktop with millions of "hooked" users and organizations...at which time it raised its prices and plans to force users to pay annual tributes to feed their dependence on Microsoft products and services.