[seanwilson]

I like the idea. How would it stop someone releasing a free version of a paid development tool though? It relies on people downloading the free tool to be honest enough not to use it on commercial projects?

[kemitchell]

No license can guarantee compliance with its own rules. That's true of all copyleft licenses, including GPL, EPL, and MPL.

Whether and how to enforce the license is up to the developer.