Yesterday evening I was chatting with a few people from ST Micro's research and development team working on security. When I asked what they do in particular, an example they gave was authenticating print cartridges. I tried to imagine the security problems around print cartridges but failing to do so asked what they were trying to protect. They explained that this isn't their business: they just implement a mechanism; how it is used is, in this case, HP's business. What HP wanted to do is detect clones (i.e., compatible cartridges). The reason they wanted to do that is not to prevent competitors from producing compatible cartridges, they reassured me, as that would be illegal. The reason they wanted to do that is that if they detect a competitor's cartridge, they can, for instance, use more ink when printing. Classic.