The new Exilim Card EX-S10 (pictured) manages to pack a full 10 megapixels, 3X optical zoom, a 2.7-inch LCD, and stereo microphones into its 1-inch thick frame -- which means we're a little curious as to how noisy that sensor is, since it can't be very big.
If you're curious about your heart-rate variability and the other data thatcanbe gleaned from it, I'd recommend the HeartMath Inner Balance for a comprehensive approach.