Like many people, I sometimes have the TV on "in the background" while I engage in some other activity. Many of the things you might watch this way (24 hour news, baseball games) have long periods of boring fluff, interspersed with important bits that you don't want to miss.
I'd like the channel
to have an out-of-band signal that indicates that the content about to come up is more urgent than normal. (Kind of like the URGent bit in TCP, for those of you who know about such things).
Your TV could be set by you to respond to this in a number of ways:
* Do nothing
* Raise the volume or take the set off mute
* Switch the main picture with the Picture-in-Picture if the small one is urgent
* If you are not watching at all, come off standby
If you use a DVR (i.e. TiVo), it could use this bit to skip to the good parts for you.
Suggested content for this would be:
* (Non-test) Emergency Broadcast System announcements
* Amber Alerts
* News bulletins of breaking stories
* Big plays in sports games
That last one is what made me think of this, watching a long, boring baseball game in PIP one day. It would have been nice to have the PIP automatically expand when someone got a hit. (And actually, there has been some research on automatically detecting this, see link).