Public domain or GNU AGPL would work, as mentioned by the other comments. I suggest doing either of these. If many companies won't touch the stuff with GNU AGPL

Public domain or GNU AGPL would work, as mentioned by the other comments. I suggest doing either of these. If many companies won't touch the stuff with GNU AGPL, they can still require a license, so you can offer a commercial license, and then there will be the payment for it. Other kind of multi-licensing with GNU AGPL is also possible.