iPhone4S
On my recent trip to China, I brought along my T1i and, for the first-time ever, no point & shoot. Left the Fuji EXR100 at home and took over 300 photos with my iPhone4S. That is indeed one nice little camera! It is not a substitute for a real camera (something beyond most point & shoots), and if you work it hard, you'll discover its limitations. But at the same time, you'll also be blown away by the things it can do.
Very impressed by what a very tiny sensor can do.