Gigapixels

Talking of high resolutions, there is already a few techniques developed allowing capture of images at incredibly high resolutions - billions of pixels (GigaPixel). First such images became to appear in 2003-2004: enthusiasts or even institutes were capturing multiple megapixel images and when stitching them on computer. Remember, where was the famous 2.5 Gpixel panorama image from Netherlands Organisation for Applied Scientific Research TNO?
Later, inventors began to capture images on big size film using home-made optical systems and then scanning negatives with great resolution, taking barriers of gigapixel or even four gigapixels at one camera shot.
Largest size I could see now is 8.6 Gpixel image viewable through flash application. I must say - all those gigapixel images look fantastic - they have a great detail - you could zoom in, and zoom in and zoom in and still get the surprisingly sharp image and see smaller details.

416 Megapixels

Better Light has announced Super10K-HS™ - digital scanning back able to create image at native resolution of 10,200 x 13,600 pixels.

A scanning back is a type of digital camera back. Digital imaging devices typically use a matrix of light-sensitive photosensors, such as CCD or CMOS technologies. These sensors can be arranged in different ways - one way where each row captures RGB components, or using one full-sized layer for each color. A digital scan back takes a similar approach to the second type of photosensor, but instead of using one matrix for each component, it uses one array per component. This translates to a 3xN sensor matrix, where N is typically a large number (between 5,000 for earlier models and 15,000 for newer models), which is then placed vertically in a holder. To take an image, the sensor travels the x axis, taking one exposure per point.

Digital scanning backs are typically used by museums or similar institutions where demand for very high detail in reproducing art originals, prevails upon the other aspects such as time of the capture and storage space.
This new Super10K-HS™ allows scanning of originals of size up to 34 x 45 inches at 300 dpi without interpolation. It is supplied with 40 Gb or 80 Gb internal hard drive for image storage, as only one image with maximum resolution results in 794 Mbytes file.

On the image below Super10K-HS™ is mounted on Cambo Ultima 4x5 camera for art reproduction.

Images from Better Light site