My algo class was with Charles Rackoff who I believe was a co-author to the first paper ever written on "zero knowledge proofs" for which he won a Godel prize for in the 90's.

I honestly can't remember much about the class except that it was really difficult and I haven't really used anything I learned from that class in my day to day. Hopefully there's something stored in my brain somewhere if I ever need to recall his lectures in the future.