Carl Zeiss Apo Sonnar T* 1700mm F4, Price unknown

The "beast" lens debuted in 2006 at the German Photokina Image Expo. It weighs 256 kg. Zeiss even developed a special focus servo control system, similar to those found on astronomical telescopes. It is also the world's largest non-military telephoto lens.

The Zeiss lens features 15 elements in 13 groups. Zeiss reportedly tailor-made it for an anonymous wildlife photography fan. Arabic letters and the emblem of Qatar imprinted on the lens have made people speculate about the possibly very extensive wealth of the buyer.

No one knows about the exact price of this lens, but rumor has it it costs more than a luxury car.