I am looking for a nice way to generate a nested site structure in ruby. I want something that I can propose to clients instead of msword documents. Something of the form:
The simplest of those I have seen is Stacey, though it does not run static content, it generates it on the fly, and its in PHP, but yeah it's just files and folders, even if you drop images or videos or pdf's on the folder they will be managed and added automatically. And they are just .txt files. http://www.staceyapp.com/
But, if I had to choose a static compiler in Ruby I'd go with nanoc. It's the most powerful and flexible I've seen and once you configure it with the rules and such, it's just files and folders too.
There is also Stasis, I haven't tried it but it seems pretty good.
http://stasis.me/
Take a look at Jekyll
Here's a gist featuring the most popular ones: https://gist.github.com/2254924
Monkeyman (Scala) supports markdown and SCAML, the Scala version of SCAML. It will basically copies and transforms a folder structure, in any way you like. Without any processing it will copy the structure as is, but it has a slew of decorators that not only are able to transform the content, but also the location to anything you like.
It doesn't support compass, SASS or any of that yet (although being based on Scalate, it probably does transform coffeescript embedded into the template pages, but I haven't tried that.)
DocPad works quite well. It supports a broad range of preprocessors.
there is also middleman for generating static sites