Some NFC chips use passive systems of powering themselves, meaning that they draw power from the electromagnetic field of the device that's attempting to read it to power it on just enough to send the information kept on it to the built-in memory.
My question is, how feasible is it to harness this small amount of power as a sort of switch to power something else on?
I was looking into the idea of using an NFC tag to turn on a computer in a project I'm working on, but it seems like the most common way to achieve this is using the chip to prompt whatever device is scanning to send a packet to a specific MAC address, one that has Wake-on-LAN systems enabled on the machine to trigger startup. This seems incredibly unintuitive to me, and also makes it easier to trace.
My idea was to exploit the small bit of power sapped into the chip to complete a circuit or otherwise function as a direct switch for an electronic system. Obviously there isn't nearly enough energy to power the device on it's own, but I'm more of looking for a system that, when activated, sends a signal to the electronic to switch on the power supply and start the machine.
Are there any devices or systems already in place that do something similar to this? I'm looking for something that can start a device passively, without the need to include traditional I/O for power control. For example, a pirate box server hidden in an inconspicuous case, that can be turned on simply from touching your phone to the surface. If there isn't, is it a feasible concept to modify a regular NFC chip for this kind of project? In theory, I should be able to thread a wire through the thin exterior to make contact with the internals of the chip, and from there, it's just a matter of finding something that can serve as a switch or complete a circuit with such a small amount of power, right? Or would diverting the power away from the board in the chip, even if it's routed right back, cause enough resistance to keep it from functioning at all? I know the amount of data and power we're talking about is ridiculously small compared to what we use for typical power consumption in electronics, so I'm open to the idea that this simply isn't possible without a super beefy chip or some other system for extracting power.
Anyone that has read extensively about NFC chips or uses them frequently, feel free to point out what a stupid idea it is, or how it will never work, or even better, make fun of me for not realizing an incredibly similar system already exists that would work just fine instead. Any speculation or feedback is appreciated.