I read your comment on roaches in a microwave. I must confess that with nothing better to do in my spare time I decided to address the never ending battle against cock roaches in the the great USA. Contrary to your suggestion that the microwave in question might have been a Popiel the one I used at the University of Tennessee Center for Health Sciences was no Popiel. As a matter of fact it was a microwave generator capable of delivering 5000 watts. At the maximum power level the microwaves have NO appearent affect on the more common German Cock Roach. I did note that the container used at first eventually heated up enough to kill the varmits but it definitely was not the microwaves. My theory is the same as the author of the question you commented on. A roach has liquids inside its exo-skeleton that should boil. The appearently do not do so in the presence of microwaves. I am still experimenting on this delima but I suspect the answer lies within or upon its exo-skeleton or “shell”.
One house hold chemical that most unwanted creatures will avoid is table salt. A well soaked rag with salt saturated water wiped across a surface will repell roaches even after it dries.