Anyways, I diverge... so your mother keeps nagging you about this great home remedy to get rid of mice, but for some reason you're just not seeing it - ammonia, really - who does that? Even better it sounds like something your neighbor from a foreign country would say, "Ammonia, get rid mice fast. Use today!"
Is there any truth to the myth? There just might be... this is another one of those your mileage may vary, but it could be a cheap and easy trick to get rid of those little rodents. In the wild mice do have some natural predators... so to naturally get rid of mice, it may make sense to use this knowledge against the little buggers. I'm not suggesting you go get cat or fox urine and spray down your walls. That will probably work (Hmmmm - maybe I should write that up - this idea could be worth millions) - I'm not sure how pleasant your new living accomodations would be though. Hey, some people like the smell of urine...
Truth of the matter is - use ammonia because it just so happens that the scent ammonia puts out, simulates the smell of urine from possible predators. So how do you do it? Take little plastic caps and strategically place them where the mice are located. Fill the caps with ammonia. Don't expect the mice to drink the ammonia... the scent put off (and it's a strong scent) will deter the mice. This method makes sense in places like the garage or attic or crawl space... probably not the kitchen. Also if you have pets, I'll recommend that you avoid this method as they may decide that they're thirsty and drink - not good!
Hope this little household mixture to rid mice helps you!