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So why don't you move if you are so unhappy?

Here's a list of possibilities:

http://www.zyra.org.uk/taxhaven.htm

the very reason that they made that band unlicensed was because it's right in the sweet spot for absorbtion by water.

in the liquid, individual water molecules are organized into transient ring structures, in which rotation is "hindered": that is, they can't rotate without banging into a neighboring molecule. Thus, there are no resonant transitions in the microwave region. Absorption takes place when the random motions of neighboring molecules allow a given molecule to follow the applied field for a short distance, after which it bangs into a neighbor, converting the motion into heat. This process involves all sorts of orientations of the molecules, and doesn't have any specific characteristic frequency but instead a wide range of frequencies: in particular, 2450 MHz plays no role, and 2300 or 2600 MHz would work just as well (but in the US the FCC would be after you). The use of 2450 MHz is a historical artifact having to do with frequencies licensed for industrial use, not related to any specific property of molecular or liquid water.

Wrong.

Might have something to do with the Microwave operating at 2.4 GHz http://www.zyra.org.uk/microw.htm which is absorbed by water better than many other frequencies and if you used it for mobile phones you wouldn't be able to use your phone when it rains. 802.11b and g (11 and 54 MBit/s WLAN) operate in the 2.4 GHz band so they would have problems working from inside your microwave oven, your mobile phone does not.

For the lazy...

Do you mean this link?

I'm sorry...I couldn't resist. :)

2.4 GHz is not the resonating frequency of water. That's way way up in the GHz chain. 2.4 GHz was chosen because that band is the junk band in which unlicensed users are subject to interference as part of the spec.

Microwaves work by oscillating water molecules, which are dipole. The magnetron cycles 2.45 billions times per second, which twists the water molecules. The interior of a microwave oven is coated with a microwave-reflecting material which allows a single beam to essentially paint the three-dimensional interior.

So many people write that water resonates at 2.4 GHz. It's just not true. Here's a nice explanation of how it works.

guys dont wear skirts

Oh really?

Only at frequences that resonate with water (2.4ghz) like your microwave oven or your WiFi card. In the case of the WiFi card it isn't a big deal since the power is very low.

That's a common misconception. The resonant frequency of water is not at 2.45 GHz (the freq of microwave ovens). There is an absorption peak around 22 GHz for liquid water. (See How a microwave oven works and the graph from Ask Mr. SETI.) Of course, the molecules of water interact more than those of a gas, so things are a bit more complicated.

2.45 GHz was chosen as a compromise that would heat water, fats/oils, etc, as well as what was easily manufacturable back then.

In any case your are very likely correct. Neither WiFi cards nor diagnostic devices will be emitting very strong microwaves.

Microwaves will work only work on one frequency, which is the frequency that water likes to vibrate at. So it's not like they can change the frequency because then it would do a crappy job of heating the food. I suppose they could be very well sheilded.

That's a common misconception. The resonant frequency of water is not at 2.45 GHz (the freq of microwave ovens). There is an absorption peak around 22 GHz for liquid water. (See How a microwave oven works and the graph from Ask Mr. SETI.) Of course, the molecules of water interact more than those of a gas, so things are a bit more complicated.

2.45 GHz was chosen as a compromise that would heat water, fats/oils, etc, as well as what was easily manufacturable back then.

So, airlines could use ovens at a different frequency, but what would be the point? They need to harden their electronics agains leaky home ovens, plus any misguided "death rays" cobbled up out of surplus microwave oven parts.