[ChiCommTroll]

Take for instance Intel's addons to IPMI "Automatic Management Technology".

Let's say you have a server, reachable on a certain network address on a LAN.

I can turn on AMT, I can set up server management answerable at the SAME address. network traffic to and from the machine and network is undisturbed.

I can install bios updates, configure aspects of the machine, all kinds of things, just with AMT. I have read in some cases you can configure the machine this way even if its powered off.