For whatever reason you might want to, you can melt a beer bottle relatively easily at your own house. The process centres around creating a hot spot on the glasses surface and then allowing the microwave to finish the job. Melting glass is extremely hot and this process can be hazardous, so proceed with caution
Remove the revolving glass tray and the plastic guiding ring from the microwave and place the bottle upright in the back.
Heat the bottle slowly in a wide general area with the blow torch. This prevents temperature shock, which could shatter the glass
Begin focusing a tiny area with the blow torch while periodically heating the rest of the area. Get this small area to start glowing red hot.
Close the microwave and set on high for an extended period of time, around 10 to 15 minutes.
Once you are finished, allow the bottle to cool inside the microwave; the rapid cooling it will undergo if removed will cause it to shatter.
Wear safety glasses and gloves at all times during this procedure. Extreme temperatures can and will shatter glass. Use a microwave you no longer care about. Plasma generated by this process can damage the machine.