"as your mother no doubt warned you, putting metal into a microwave can be dangerous."
Will someone please explain to me why putting metal into a microwave is considered dangerous? Metal simply reflects microwaves, just like the walls of the cooking cavity.
Wives tail?

Mr. Hart, http://engineering.mit.edu/live/news/1041-why-cant-we-put-metal-objects-in-a-microwave

My understanding is that it could reflect the microwaves back into the magnetron and burn it out. Just ruins your microwave, that's all.

@ Charles: Putting metal objects in a microwave can be dangerous because the temperature of the metal can reach dangerously high levels. Very thin metal sheets can usually disperse that heat before becoming dangerously hot. But a chunk of metal are more dangerous because heat at its core cannot quickly dissipate. Below is a link to an article on this topic by MIT Professor Caroline Ross:
http://engineering.mit.edu/live/news/1041-why-cant-we-put-metal-objects-in-a-microwave

All you have to do to melt metal in a microwave safely is encase the microwave with silicon carbide. What happens is the microwave energy gets absorbed into the silicone carbide allowing intense temperatures to melt metal without the metal reflecting and destroying the microwave. :)

ok, first what a load of krap, I use my old microwave to melt silver and gold into investments for my jewelry all the time, its a no bubble in your casting and no need to spin hot stuff in a circle or use vacuums to cast stuff with no blown anything just use vent tape to cover vent inside to magnetron to prevent it heating up and bango a nice little blast furnace can be had...the above old wives tale of DANGER DANGER WILL ROBINSON is lame, pay attention and its fine

Kalab Hayes Wood FYI all you need is a piece of duct tape over vet hole inside oven and you can melt metals do it daily

Do a search on YouTube and you'll find plenty of examples of people melting lead in their microwaves with no apparent side effects and their microwaves are still functional afterwords.

has no one here cooked a pizza in a wave ? the trick is to use foil and cut a hole in the center of the foil to quicken the heating of the center of the pizza, now I personally only have done this about a thousand times or so. I found the trick was to have more food than metal. The important thing to remember is boiling water, it can blow up in your face. OUCH ! not fun, and my mom who knew better did it for the first time a few years ago.

I sure as heck would not do experiments with metals and then use the oven for food. But as far as things exploding go eggs can be rather nasty, make a mess, and maybe burn you as well if they explode after extraction from the oven. I know how to avoid an egg explosion but have never solved the shards of egg that stick to a ceramic bowl of egg in a microwave. Trying to scrub that ceramic is not a trivial effort.