Definitely fits the bill: * Python-like syntax * Compiles to C/C++/JS/Object-C * Supports Windows, Linux and Mac. * Multithreading * Extensive metaprogramm

Definitely fits the bill: * Python-like syntax * Compiles to C/C++/JS/Object-C * Supports Windows, Linux and Mac. * Multithreading * Extensive metaprogramming * VERY fast compiler * Dead code elimination * Very strongly typed, with related features (eg distinct types) * Type inference * Excellent structural generics, type classes, and compile-time concepts Basically looks like python, runs like C. Because it compiles to C, you can run it anywhere you have a C compiler (which is almost anywhere).