Clojure - a dialect of LISP that targets the JVM (and CLR and Javascript).
Features SoftwareTransactionalMemory, FirstClass immutable structures designed for sub-structure sharing (needed to make STM remotely efficient).
It is designed to be a general-purpose language, combining the approachability and interactive development of a scripting language with an efficient and robust infrastructure for multithreaded programming.
Philosophy
CategoryProgrammingLanguage CategoryFunctionalProgramming CategoryLisp