I think the MPL is a useful license as well, and underrated/underused. It's less viral than the GPLs when just using the licensed work, and less permissive tha

I think the MPL is a useful license as well, and underrated/underused. It's less viral than the GPLs when just using the licensed work, and less permissive than MIT / BSD because changes have to be open sourced, when the program using the changed library is distributed.