My friend Alyssa is playing with the "Smile Shutter" mode of my new camera.
The Sony A55 has a mode where the camera detects in real time if there is a smiling face in the picture, and as soon as the camera sees a smile, it automatically takes a photo. It is possible to set the "smile sensitivity" to only detect big smiles, or to trigger on small smiles. There is also a real-time smile-intensity meter on the LCD display (Alyssa managed to set it to maximum with her irresistible smiles!).
As you can see, it does work!
I assume that this mode is designed to help people catch the elusive smiles of their todlers :)