[Wlug] SSH without passwords

I remember someone talking about sharing keys between systems so you can ssh around at will without needing the password.... we are trying to do this, but are having a hard time. Anyone have a good doc (or willing to write one) about how to do this? Basically we are ssh-keygen -t (dsa/rsa) the keys, copy them to the "remote" servers ~/.ssh/ There are conflicting doc's at this point...some say you need an ssh-agent, some don't mention it. Some use passphrases, some don't. But if i have to enter an ssh passphrase everytime, why not just use the account password? Any advise would be helpful... thanks as always.. Mike