Can it be used with Hotmail, Gmail, Yahoo?

I now this is a dumb question…
Is it possible somehow to use CASG with hotmail, yahoo, gmail, etc?

Someone had to ask. 88)

For now it is possible only with owned domains.
The restriction is in ability to change MX record for the domain.

So no - for
But if you have write access to DNS MX record for - then yes.