Letting Out The Magic Smoke

Yesterday I was making a voltage divider circuit with a potentiometer on a breadboard. I planned to solder it down and use it as a variable power supply when prototyping. I was fooling with some of the leads (with power on) and I think I created a short-circuit on the metal case of the potentiometer. Anyways, it began to glow red under the dial (no, they're not supposed to glow) and let out some magic smoke. It also began to smell funny... luckily, it still works!