I've seen other replies highlighting Lisp in general and Racket in particular, but when it comes to a "little language" I think it's valuable to have a link to

I've seen other replies highlighting Lisp in general and Racket in particular, but when it comes to a "little language" I think it's valuable to have a link to Paul Graham's article on The Roots of Lisp: http://www.paulgraham.com/rootsoflisp.html http://www.paulgraham.com/rootsoflisp.html It underlines all the points already made here about Lisp, and also includes a CL version of the original code. 67 lines including comments and empty lines. Endless possibilities.