> http://utilitymill.com/
>
> With Utility Mill:
>
>     * Inputs and outputs are handled for you automatically
>     * You just supply the Python code that does something new
>     * You get a RESTful API for free (XML and JSON)
>     * You get revision control for free
>     * All utilities are open source (GPL)

Sounds a lot like Balloon that _why made.

http://balloon.hobix.com/

Cheers,
Matt