The new bytecode for the internet
You are probably looking for webassembly on github. Or on wiki or on HackerNews
The whole purpose of this repository is to save you one more Google search; it can be removed once github creates an alias webasm->webassembly ;)
Play an impressive demo of native wasm in your browser now. Or a new even more impressive demo if you have a fast machine.
Check out a wasm Hello World
https://github.com/mbasso/awesome-wasm
https://github.com/appcypher/awesome-wasm-langs
To generate binary wasm yourself, see binaryen, wabt or emscripten. Soon you can just use your default clang to compile c to wasm (right now you need the latest versions of llvm/lcc to do so)!
WebAssembly is not a binary bytecode format for standard js. There are reasons against overly specialized bytecode. However all browsers could and should come with a compressed javascript AST reader. Someone please specify the 'jast' file format.
Compile Ruby, Python, C++ -> LLVM -> asm.js -> binary.wasm and load it with native speed in current(!) browsers, or in old browsers via polyfill.