I had mentioned in my Solar Badge post that I had tried to replicate the sun to power a Solar Badge and could not. I improved my method (by placing the HID lamp in a driving light reflector) and achieved full voltage, but not full amperage. You can see in the pictures below, the Solar Badge will put out 5V at 40mA without question. In this quick video you will see an HID light powering a Solar Badge as well as my ATX power supply failing and quickly (and time lapsely) preparing another one.
Bench-top power supplies are a great way to safely power your projects. ATX power supplies are good, but I don’t always want to pump 22 A ( yes, 22 amps) into my project. A good bench-top supply will limit current so you don’t feed your project too much. A decent bench-top supply will also tell you how much power is being consumed by the load it is connected to, a handy display to keep an eye on how much juice is being consumed by your project. My particular supply is capable of 0-30V and 0-5A. Plenty of power for most of my projects, outside of powering HID headlights of course..