Nice example of how Lisp code can be fast; it just tends to seem to be slow in the hands of those who don't know how to make it fast, or who want it to be slow.
I never used one, but I'm pretty sure I've been in the same room as one (having once worked for a DEC dealership who installed and maintained various PDP machines).
naver/lispe: An implementation of a full fledged Lisp interpreter with Data Structure, Pattern Programming and High level Functions with Lazy Evaluation à la Haskell.
Yet another Lisp. I'm all up for yet another Lisp.