* Automated injury detection. You've got a warehouse, you've got cameras, now you've got an instant alert when one of your workers appears to be injured but out of sight of other workers. You've got street cameras, now you've got automatic detection of someone having a heart attack and laying down on a sidewalk. (Dystopian application: "homeless person detected, deploying zap-drones") Hospitals and old folks' homes could use this, too.
* Lifeguard Assist programs - automatic detection of drowning-like behaviors. (Of course, over-reliance on this would be bad...)
* Children separated from parents might be easier to detect in places like malls, etc. (I'm going to stop listing obvious parenthetical dystopian applications)