I made the website for my wedding with Redbean, just for a bit of fun. It was a delightful experience. Deployment was just: upload one file, restart a process. I developed on my Mac, and deployed the executable, unchanged, to a Linux server. It just worked. Nice.
Yep, for some reason my imagination is just not kicking in here. What can I do with embedded Lua in backend? I'm not familiar with Lua at all so I have no idea.
Well, couldn't the same question be asked about using Python or Ruby within a server? It's scriptable, easier and faster to iterate with. Dynamic. You can execute Lua scripts in Redis. LuaJIT and other implementations can be incredibly fast and pretty fun to code in.