The EBR-1 museum also has the world's only nuclear powered jet engines. These engines were designed by the department of defense during the 1950's to be used to power gigantic bombers which could fly around the world never needing to refuel. This was at the height of the cold war. The bombers were never built, but the jet engines were successfully tested several times in the Idaho desert.
We enjoyed a tour of the EBR-1 site -- all the original equipment, cooling systems and control consoles were still in place in the original building, including the employees lounge area with the 1950's TV!
(Thanks to Jim for supplying the text for this post.)