You can do some nice things in Lua [1], but the one I'm most interested in at the moment is probably Terra [2]. Its concept is that it's a language like C, but uses Lua as a sort of preprocessor Language, so you can use complex macros, templates, etc. There's even a java-like class-system, if I remember correctly.
[1] https://github.com/darkwiiplayer/moonxml
[2] http://terralang.org/