One of the best teachers I had at Caltech. Though, given that this apparently happened in May I'm not sure why it's being posted today.
I was looking at some of his work, and saw that he had died. I didn't remember hearing of it, and searched for an hn discussion on it (as there are usually some excellent stories pertaining to the person; a good reason to read hn.) It hadn't been posted, so I did. Sure enough, someone who knew him.
McElice's cryptosystems, while a bit unwieldy in terms of key sizes (order of magnitude: 512KB), is not susceptible to the quantum-computer-based attacks like popular schemes used today.