I see jdp has beaten me to suggest K, trust me that one's good. The other suggestions (Erlang, Lua, Clojure, Ada...) strike me as pretty tame, not very interest

I see jdp has beaten me to suggest K, trust me that one's good. The other suggestions (Erlang, Lua, Clojure, Ada...) strike me as pretty tame, not very interesting to talk about. Here's a heap of important far-out languages that nobody mentioned yet: - AspectJ (program modification by aspects) - SNOBOL (language-integrated grammars) - Raph Levien's Io (continuations and coroutines, not to be confused with Steve Dekorte's Io that you mentioned) - PostScript (concatenative language, widely used) - LabVIEW (graphical dataflow language, widely used)