The following video is a little old (2007), but it gives a flavor of some of the neat things that can be done with just a single LuaTeX feature, "attributes":

The following video is a little old (2007), but it gives a flavor of some of the neat things that can be done with just a single LuaTeX feature, "attributes": http://river-valley.tv/luatex-attributes/ http://river-valley.tv/luatex-attributes/ (executive summary: attributes give you the power to transform portions of the document, from characters to specific words or paragraphs or the whole document in various ways, like assigning them a certain color) And here is something that covers LuaTeX from a more general perspective: http://river-valley.tv/luatex-a-users-perspective/ http://river-valley.tv/luatex-a-users-perspective/ (executive summary: programming TeX directly is hard, doing the same in Lua is easy, and LuaTeX lets you program TeX in Lua)