http://www.mahoodsculpture.com/jim-sanborn-sculptures/

did anyone can solve the KRYPTOSE ridles?
Kryptos is a sculpture by American artist Jim Sanborn located on the grounds of the Central Intelligence Agency (CIA) in Langley, Virgini..the sculpture continues to provide a diversion for some employees of the CIA and other cryptanalysts attempting to decrypt the messages.
At least one of them was. I think 2 remain unsolved. The encoder is still alive.
ADD: Nope, there’s 4 codes (or “parts”), and 3 have been solved:
http://en.wikipedia.org/wiki/Kryptos
Kryptos – CNN 2005