Microwave ovens are all well and good, they have their uses and their faults... mainly that they're a bit clanky- beepy and inflexible in terms of how you can use them.
Now, consider this: A Pot/pan lid with a whacking great cavity magnetron on top. It should be quite large and have a series of steps in the underside to allow it to fit many sizes of vessel. There will also be a series of interrupted radial conductors, these will function to ensure the device only works when it is in 360 degree contact with a a conductive surface (the pot must be metal, see?).
Then, you can just have it around the kitchen for when you need a bit of a boost in anything aqueous. Such as getting large amounts of water for pasta/potatoes up to temperature a little faster. Or for heating large pots of chilli etc, where the viscosity prevents convection from spreading the heat around.... and more heat on the bottom just means burning.
Probably better for commercial kitchens than regular ones, maybe make it about 6kW from a 3-phase supply.-- bs0u0155, Mar 29 2013 A conventional heating element would really work in the Infra red, I'm looking for a bit of penetration here.... also, that lid would get super hot...-- bs0u0155, Mar 29 2013 Add a piece of stove pipe to your magnetron lid, and presto! Instant microwave/radar jammer!-- lurch, Mar 29 2013 Or 6kW burglar deterrent?-- bs0u0155, Mar 29 2013 I think that was where Bussard's beryllium fusion reactor (which emitted microwaves) fell over: the statement "can be of any size" = instant microwave weaponry.-- FlyingToaster, Mar 29 2013 random, halfbakery