Nox
Nox was ported for web browsers, including Multiplayer using WebRTC!

This project uses WebAssembly as it ports the Source code of Nox, using Emscripten. This is quite notable, as it proves that WebAssembly can bring these large C/C++ codebases using Emscripten to the web, to run impressive 3d games.
If you are interested in porting C/C++ libraries or applications, I'd highly reccomend Ben Smith's (binji) SFHTML5 Talk on porting C projects to the web. This talk is unrealted to D3Wasm, but can help drive what goes into porting these types of applications.
Additional Resources
Date Added: 11/22/19