Is there a way to contact the owner of an ethereum address?

I would like to contact the owner of an ethereum address. What are my options? Sending a transaction with message data is not an option for obvious reasons.

I am aware of http://about.inb0x.life however, I doubt that the address owner uses their service. Even if the owner uses it he/she will not get notified about the message.

Leaving a comment on etherscan will probably also go unnoticed.

Are there any other alternatives?