When mine went out I was driving and got a warning beeping and warning light. I could smell melted plastic, I was close to the shop and ran back.
When I got there I shut it off, popped the hood and it was smoking. Then noticed a couple seconds later it was melting my positive battery cables.
I ended up cutting the cable to the alternator with bolt cutters. It would have burnt to the ground if I just pulled into the gas station I about did before driving back.