As part of the SPICE project there was an implementation of Lisp on the machines. This implementation became CMU Common Lisp. CMU Common Lisp is still available, but it also served as the jumping off point for Steel Bank Common Lisp (SBCL) which is today the top free Common Lisp implementation.

It's interesting there's a heritage of code stretching all the way back to these old machines, although of course the changes since then have been massive.