Micro-Nikkor 55mm f/3.5 @ f/8 - this lens is predecessor of more famous Micro-Nikkor 55mm f/2.8 Ai. The later has slightly more CA.
This is the lowest chromatic abberation I've measured on any lens so far using Nikon D70 and Imatest. The result should be taken with the grain of salt, as the RAW conversion was done using Imatest's internal DCraw converter which does exibit some colour abberation of it's own. When converting RAW files with some other converters, even lower figures can be obtained.