Signal Cell Phone Advisor
Stop the ringing… but dont miss that call. We think that’s a great idea.
It apparently can tell when your phone is ringing by detecting radio waves (we assume this is when your phone is on silent), and proceeds to light up to alert you that there is a call. This wont work from across the room very well, but might be useful when you are concentrating at your desk and only want to be interrupted if you happen to notice. Sure, ringing is great when you want to be distracted, but if you only want to talk when you need a distraction, this might be the way to go.
Available here for $21.