Few of these lenses exist; Sports Illustrated magazine owns two of them, as does Canon Professional Services and James Jannard, the billionaire founder of Oakley and RED Digital Cinema. Recently the New York based B&H Photo retailer listed one for sale in their "Used" department for $120,000.[3] Up Close with the Canon EF 1200mm f/5.6 L USM Lens[4].
From Wikipedia. Wow, would love to test one...