For people who think that even the Fuji X10 (see posts below) is too large, for those who prefer a real breastpocket-camera which disappears when it's not needed, I think the brand-new Canon S100 should hit the spot. Very rarely is so much quality and so many professional options (Shutter- and aperture-priority, RAW capture, etc) placed in such a small body.
I have the Canon S90 which I love. The S100 has slightly longer zoom (5x vx 3.8x), more pixels, 12MP instead of 10MP, and HD video recording.
It's also available in "silver". The photo is from this review.
... Actually when I heard that the S100 had a longer zoom, I immediately had doubts, this (and the tighter pixels) might affect image quality. And in fact the above-linked review confirms that the S95 has the edge in pure image quality. And one is likely to find it cheaper! (It should be said that the PhotographyBlog review disagrees with the image quality assessment, though. I'm sure they're both very good.)