I pirated an enormous amount of software (mostly games) as a kid for the Apple //e; there was a thriving gift culture around that kind of thing back then, and it seemed "normal". I grew out of that, but now I use open source software almost exclusively for my personal and professional day-to-day. There are very few pieces of software I've paid money for (directly; clients and employers are a different story), and most of them are in the "distractions" camp (iPhone games, indie titles for Linux).

That being said, there are a few pieces of commercial software I've used in the past for which there are no serious viable open source competitor, nor do I expect the level of interest in those areas to rise to the occasion. One example is IDA Pro; it's possibly the worst user UI I've ever had the displeasure of using, and yet there's nothing that comes even close to competing in it's niche. It's expensive, especially if you need support for an obscure processor, because the market for it is so small; but, if your day-to-day involves reverse engineering, it's worth every penny.

At one time, I'll admit that I had access to a pirated version of it; the price presents a significant barrier for an enthusiast, and a casual search of any torrent site will turn it up. It was easy to obtain. There's two things I took away from that.

First, I felt guilty about it, as I know Hex Rays (the company behind IDA Pro) is really only a couple of exceptionally dedicated folks who haven't priced their product the way they have to screw me, but because it was the only way to make it viable at all. There's two major users of IDA: reverse engineering professionals who won't have a problem with the price, and black hats who won't pay for it at any price. The price is, therefore, what it has to be to assure continued development, and I think most reasonable people can see that.

Second, I realized that the functionality I was using was only a small fraction of the whole product, so I implemented what was necessary for myself (in this case, an SH2 disassembler), and eliminated the guilt: the rest of the features were nice to have (multi-arch support, decent navigation, awesome graphing, x86 de-compilation support, etc), they weren't nice enough to warrant $1000 for what amounts to a hobby for me. I haven't used IDA since, and learned a lot about building an intelligent disassembler.

I see a few other products in this niche: Solidworks, Pro/E, MasterCam, and to a much lesser extent, certain pieces of Photoshop and the VMware ecosystems. All vertical-market applications that average folks don't need, but hobbyists would love to have access to (but are stopped by the price). In both the Photoshop and VMware cases, hobbyist-level versions have emerged (Photoshop Elements, VMware Server/Player, etc.) as a direct reaction to open source software eating away at that hobbyist market that builds their brand (GIMP, Xen, KVM, etc). In the cases of software like Pro/E, no such reasonable competition exists, so the pricing is what it is, and the hobbyist be damned.

I'm not sure if I'm actually going anywhere with this little story (other than incriminating myself, and probably assuring that I'll never be able to legally procure a copy of IDA at some point in the future), but perhaps someone can glean something useful from it.