If you think documents should be programmable, you’ll love it.
If not, you can move along.
Pollen gives you access to a full programming language (Racket) with a text-based syntax that makes it easy to embed code within your documents.
Using Racket 6.0+, install from the command line:
raco pkg install pollen
And update like so:
raco pkg update --update-deps pollen
Official mailing list: http://groups.google.com/forum/#!forum/pollenpub