Speaking to his comments about Nginx, Cloud Foundry's routing tier does dynamically reconfigure Nginx without reloading the config files using some clever Lua code. WebSocket support has also been added to Nginx core.

There is a similar effort underway to port Hipache back to Nginx/lua: https://github.com/samalba/hipache-nginx

It's still experimental but from what I saw, yeah, the Nginx+Lua combo is pretty cool.