I didn't post "Links" topics for a while - that's of course not because there're no interesting projects around, but because there're too many and you can't keep up with them ;-). Anyway, not collecting links to them doesn't help either, so:
- openFrameworks - C++ framework to glue together ~20 well-known technologies and libraries, mostly for visualization, UI and multimedia (all collectively "creative arts coding")
- Cinder - Another C++ contender from the similar area
- Emscripten - "An LLVM-to-JavaScript Compiler" (C, C++ compilation to JavaScript)
- asm.js - "An extraordinarily optimizable, low-level subset of JavaScript", from Emscripten authors.
- "List of languages that compile to JS"- from CoffeeScript authors.