Racket-auto-keywords.vim is a project mainly written in Vim Script, it's free.
Populates syntax keyword racketFunc/racketSyntax/scribbleMarkup
This is a mirror of http://www.vim.org/scripts/script.php?script_id=3757
This script works with racket.vim (and scribble.vim if you have it [vimscript #3756]) to automatically populate the syntax keywords lists
Issues:
Currently, I can't get this to run in an autocommand, so I have it bound using control-F4
Anyone who can get this to work with scribble.vim, without vim SEGVing -- please contact me.