Fished writes: "A couple of recent articles here on Slashdot have made reference to Functional Programming, which forces me to admit a weakness. Despite programming since the age of 6 (literally) and using snippets of Emacs LISP for almost 20 years, I've never really mastered a Functional language. Since I learn a new programming language every year to keep from getting stale, I've decided that this year I'm going to correct that. So, here's the question: first, what's the best language for a new-comer to functional programming? I recognize that Python and Ruby incorporate some functional features, but I want to learn a pure functional language that will force me to master the functional paradigm. Obviously, LISP is a choice, but I'm not sure that its the best choice. Ideally, I want a language and an environment that will let me write something useful. Second, what books, websites, and tools would you recommend for someone new to Functional programming?"