We're developing an application which requires a small light to be controlled by a PC running Windows XP. We're looking at our options in terms of connections and power supply. Our first prototype was controlled via the serial port, but required a wall plug. We're trying to reduce cost and outlet usage, so we need an alternate strategy.
What do I need to know in order to prototype a USB controlled light. From my preliminary research, it looks like a USB 2.0 bus provides enough power to light up our light sufficiently. What do I need to do to get a light controlled via USB and what requirements do I have in my software to do said controlling.