It seems that a "government" has been infecting the firmware on hard drives with viruses.
This kind of attack is extremely potent as it can reinfect the machine every time it is turned on.
My main problem with this is that every time some government has created some super clever piece of software like this, it has soon fallen into the hands of the very unscrupulous. Especially where they can take the firmware, replace the spying program and then use normal vulnerabilities to apply that firmware to your hard drive. In effect creating a perpetual virus you can't get out even with a clean and re-format. You could only either apply the clean firmware (if you know how), or buy a new hard drive.
Whilst I applaud the ingenuity of the security services, I do wish they wouldn't impact us in this way. It's been a long time since viruses attacked the PC motherboard BIOS itself and manufacturers had to create a lot more protection there. It now looks like they're going to have to create much more protection on the hard drives themselves.
Another one to add to my list of "fixes" to apply...