Fire alarm systems need to be inspected, tested and tagged annually. Testing must include all smoke detectors, manual pull devices, annunciators, visual indicators and strobes, control units, voice/alarm communications systems and any other devices that are a part of the fire alarm system.
it will need a port like this one to get more power from the usb since it only give 5.0 volts and this powered usb give up12 to 24 volts so you dont have that in a laptop and there is no way it could raise the power on the usb port in a laptop without damaging something .http://en.wikipedia.org/wiki/Powered_USB.
you said..: Power almost anything off USB Port, well powering my house didnt work. just for future reference. This is wrong. If your circuit requires 3V nominal and a maximum of 4V then you could not use a 5V USB port to power your circuit.. You risk destroying your device. If your circuit requires 7V you could still use 5V to power the circuit.