Assemble

Static site generator for Grunt.js, Yeoman and Node.js. Used by Zurb Foundation, Zurb Ink, H5BP/Effeckt, Less.js / lesscss.org, Topcoat, Web Experience Toolkit, and hundreds of other projects to build sites, themes, components, documentation, blogs and gh-pages.

Why use Assemble?

1. Most popular site generator for Grunt.js and Yeoman. Assemble is used to build hundreds of web projects, ranging in size from a single page to 14,000 pages (that we're aware of!). Let us know if you use Assemble.
2. Allows you to carve your HTML up into reusable fragments: partials, includes, sections, snippets... Whatever you prefer to call them, Assemble does that.
3. Optionally use layouts to wrap your pages with commonly used elements and content.
4. "Pages" can either be defined as HTML/templates, JSON or YAML, or directly inside the Gruntfile.
5. It's awesome. Lol just kidding. But seriously, Assemble... is... awesome! and it's fun to use.

...and of course, we use Assemble to build the project's own documentation http://assemble.io:

For more: hear Jon Schlinkert and Brian Woodward discuss Assemble on Episode 98 of the Javascript Jabber Podcast.