Here is an interesting (but somehow useless) thing to test with wifieye:

If you have a microwave oven then start wifieye and go to 'time graph'. Then put n900 inside the oven and close the door. The microwave oven uses microwave radiation at 2.45G which is near the 2.4G of 802.11b/g and its surrounding is very insulating at that frequency. If all goes well you should see the line of your wifi signal drop to near zero (or even disappear) when you close the door.