Phrozn is static site generator written in PHP.
The idea is very simple:
You write text files in your favorite format (Textile, Markdown, Twig, Haml etc), in your favorite environment (Vim, Vim, or Vim etc), spice them with styles (again, in format of your choice - CSS, LESS, or SASS), feed all this to Phrozn, and it will create static HTML site ready to be published.