I recently exposed Ektachrome 100, expired 3/1987.
Magenta color shift. Example below:
Note that near the middle-center of the slide, the colors are more or less correct.
That is a picture of my high school. :)
I shot some old Kodak Ektachrome 100 (frozen since new) in 4x5 last summer. This was 4x5 samples (so no printed expiration date) from the mid nineties in the two sheet ready load format. I put the exposed film in the freezer and promptly forgot about it. Developed them over the weekend and they turned out really nice. I really like the lower contrast verses the my normal Provia. I'll be shooting more of this for sure (assuming I can get more E6 chemistry).