Rackup is a project mainly written in Vim Script, it's free.
Syntax file for Rackup (config.ru) files
This is a mirror of http://www.vim.org/scripts/script.php?script_id=2994
It defines rackup files (*.ru) and turns on Ruby syntax highlighting on these files. Added "use" and "run" as keywords.
It also works nicely with tComment ( vimscript #1173 )
inspired by the Gemfile syntax file by ujihisa ( vimscript #2912 )