It would be a silly license. I imagine reading aloud a message on a billboard would be ruled fair use. Republishing of your message by an unauthorized party cou

It would be a silly license. I imagine reading aloud a message on a billboard would be ruled fair use. Republishing of your message by an unauthorized party could be infringement, but your license doesn't change that; the default ("no license") is "all rights reserved" so redistribution is already forbidden.