You've probably never seen a camera like this before. Sigma's new DP2 Quattro camera comes with an unconventional extended grip, like with its predecessors, the DP2 is a fixed focal length camera with a large APS-C sensor inside. This newest version comes with a 30mm (45mm in 35mm equivalent) f/2.8 lens.
But the DP2 isn't just different on the outside, the inside is also dramatically different. From the start, Sigma has used Foveon image sensors which work differently from the Bayer filter image sensors found in almost every other digital camera. While Bayer filter sensors capture light horizontally, Foveon sensors capture light vertically with three stacked photodiodes. Generally speaking, Foveon sensors can capture color more accurately, and since they don't have an optical low-pass filter, can also capture more details in a picture. However, they've also been known to shoot noisier pictures at higher ISO settings.
The next generation Foveon X3 Quattro sensor has been redesigned to only capture the full 19.6 MP luminance resolution, while the lower two layers will capture 4.9MP as color information. With the new design, Sigma claims that the Quattro sensor can deliver "30% higher resolution".
There will also be a wide-angle DP1 Quattro at 19mm (28mm in 35mm) and medium telephoto DP3 Quattro at 50mm (75mm in 35mm). Prices and availability have yet to be announced.