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)
No, Balloon (though a brilliant piece of work in its own right) is a
lot more sandboxy. Utility Mill seems to be encouraging an actual
ecosystem of python microwebapps - things you put out there for actual
people to use and interact with, not just fun demos.
martin