How hot can a microwave heat something?

"Unwise" Microwave Experiment
A question on Quora got me started. An answer to the same question on Reddit pointed to the above video. I remember staying at my parents apartment in Austin about a zillion years ago. I woke up in the middle of the night (not unusual) and thought to fix myself a cup of tea, so I put a cup full of water in the microwave to heat it. I didn't heat it that long, maybe a minute or two, but when I reached in and picked it up by the handle I discovered that the cup was red hot and I wanted to yell and drop the cup but everyone else is sleeping and I don't want to wake anybody, so I stifle myself until I could put the cup down. The water still wasn't hot. So. Some materials get hot in microwaves and some of them do it very quickly. The cup was Corning Ware of some sort. We have some and I heat food on it in the microwave, but I am careful when I take it out, especially when I use the reheat button. I kind of like having a hot plate.

If you heat up your food in a microwave safe bowl, which I presume means that it doesn't get hot in a microwave, then when you pull it out of the microwave, the relatively cool bowl is going to suck the heat out of your food, and it's going to be even worse if you pulled it out the fridge. So I like using Corning Ware.