Textgenshi.vim is a project mainly written in Vim Script, it's free.
Syntax Highlighting for Genshi Text Templates
This is a mirror of http://www.vim.org/scripts/script.php?script_id=3672
This file adds syntax highlighting for Genshi plain text templates (see vimscript #1869 for XML template support).
See: http://genshi.edgewall.org/wiki/Documentation/text-templates.html