What you can - and cannot do - with your software is often determined by the code owner's license. From not using open source APIs with closed-source digital rights management (DRM) to being barred from fiddling with Windows source code, we've seen it all.
Or have we?
ExtTLD, for developing components on the open source Ext JS framework, has been released under a license apparently suited only to vegans, vegetarians and animal rights activists.
Among the terms, ExtTLD cannot be used in connection with the development and manufacture of products that involve animal testing, products whose ingredients might come from testing on animals or genetically modified organisms involving animal genes.
That means you can't be involved in testing and neither can your products or services.
"Animal product" in this case is defined as a whole cornucopia of items spanning meat, seafood, honey, fur, silk and eggs.
Also out is participation in animal-based sports, such as rodeo riding, and transport of animals - so there go the haulage sectors and, possibly, anybody developing sat-nav systems and applications.