cell phones should have a feature where by if the phone is on ring and there is a lot of ambient noise outside then it automatically switches to the ring+vibrate mode. My Mac does this with ambient light for the keyboard. Of course the feature could always be switched off.-- nomadic_wonderer, Aug 07 2007 The competition Ringtone_20Earring [normzone, Aug 07 2007] Thanks, [nomadic_wonderer]. I have an idea in the same neighborhood I've been trying to get around to posting, and this shows me the correct category.-- normzone, Aug 07 2007 My old cell phone had a vibrate mode at the highest sound level. But I think the idea is really for automatically setting the ring volume.-- DrCurry, Aug 08 2007 I've thought about posting something similar in the past, with altered volumes for different environments. Particularly useful for office + factory jobs, where an appropriate ring volume is difficult nay impossible to settle upon.-- Texticle, Aug 08 2007 random, halfbakery