Introduced in 1976 and discontinued in 1998, the Nikon 13mm f/5.6 is often dubbed "The Holy Grail" because of its ultra-wide angle of view with minimal distortion. It was only available via special order during its production run making it one of Nikon's rarest lenses.
However, eBay (via UniquePhoto – 100% Positive Feedback) has a Nikon 13mm f/5.6 AI-S Lens available for $24,999.99 with free shipping.
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The serial number of this particular lens translates to a production year after 1982.