Holy shit. Here I figured that high-density discs would actually be more fragile than CDs and DVDs. But apparently you can take a pad of steel wool and scrape the hell out of a Blu-Ray (in this case, ...

Here's how to safely set steel wool (also called wire wool) alight using nothing more than a 9V battery. It's not difficult but you must take care as the wool and the dish can get very hot - adult ...