This probably could have been posted in the ringtone section, but since it is app specific related, I put it here. I am currently using this alert for BeWeather, but could be used for any weather app that allows for a custom notification tone.
It is the alert used by the National Weather Service in the USA when there is a warning broadcast. I find it to be very fun to use, and usually will get a conversation started about my BlackBerry, and how cool it is to set tones like this for certain apps.
