I think its a pretty cool way to get a quick front end. I don't know exactly the market for this sort of tool but I could definitely see it being useful. One thing though, some of the examples ask for login information to a website to display some metric. This sounds like it would be a good way to steal people's information so you may want to think a bit on maybe warning users not to enter info, or have to option to view the source.
Ok. I wonder if it needs to be optional if we let you create private, environment variables for your script. Wouldn't show up on view source. Or maybe we do both :).