Hi Jim,

that is a very nice feature, Jim.

Please forgive me my noob questions:

How is the signature created?
Is it possible to derive from the signature the private keys?
Does a signed message cost something?
Who receives the signed message?
Is it send to the whole bitcoin network?
Or do I have to copy it to e.g. an email?

Could you come up with some use cases?

Is it possible to verify that a payment address is untampered by an attacker?
How would this work?

Is it possible to set up contracts?
How would this work?

Is it possible to proove that I control a specified address?
How would this work?

Is it possible to create multisignature addresses with this feature?