I know where you're coming from, and I've had the same reaction to a few other similar posts on HN, however before I posted that reaction I realized two things:

1. If it's on the front page of HN then a lot of other folks around here probably know what it is already.

2. If it got voted up fairly quickly, it's probably also a big or important technology that I should familiarize myself with, at least superficially.

QEMU (short for "Quick EMUlator") is a free and open-source hosted hypervisor that performs hardware virtualization. QEMU is a hosted virtual machine monitor: It emulates central processing units through dynamic binary translation and provides a set of device models, enabling it to run a variety of unmodified guest operating systems. It also provides an accelerated mode for supporting a mixture of binary translation (for kernel code) and native execution (for user code), in the same fashion as VMware Workstation and VirtualBox do. QEMU can also be used purely for CPU emulation for user-level processes, allowing applications compiled for one architecture to be run on another.

http://en.wikipedia.org/wiki/QEMU

You could have found out quicker than typing the comment. The honourable thing to do in this situation is to find out and then post a helpful link for others.

Well, to be fair it's a QEMU newsgroup and its full listing is gmane.comp.emulators.qemu.

It's an emulator for a wide variety of hardware platforms. You'd care if you wanted an emulator for a platform it supported.

I get and share this complaint for random new startups that nobody has ever heard of before, and where the link is to the page that should be telling me what it is.

But this is an old, well-known project. If you put "QEMU" into Google, literally every single hit in the first page of results is about it.