Liskov's work on programming languages is (of course) well known. She then switched research topic to distributed systems and among other things developed the "Practical Byzantine Fault Tolerance" (PBFT) algorithm.

I thought this was interesting, because like 10 years ago I had never really heard of her distributed systems work, and kindof thought of Liskov as a one-hit-wonder. But now in the last few years PBFT is suddenly pretty hyped, because it's a key part of a bunch of new blockchains, so maybe she was far ahead of the curve...