Look how old this is! I post at SearchCommander.com now, and this post was published 18 years 4 months 16 days ago. This industry changes FAST, so blindly following the advice here *may not* be a good idea! If you're at all unsure, feel free to hit me up on Twitter and ask.
A while ago I wrote about cellular phone ringtones that adults cannot hear (for instant messages and phone calls), after seeing a demonstration on morning TV. Now, my 9 year old has verified it to be true!
I found a website, where you can test yourself, and even download these ringtones to your phone. I tried tricking my son, after he claimed to be able to hear ones that I could not, but he got it right 100% of the time. Test yourself… http://www.ultrasonic-ringtones.com/
Hehe nice, it works for me 😉