This just in: Keychain rocks

It’s a bit stale now, but if you use PAM, you could also look at pam_ssh … it allows you remove the password from your login, replacing it with your private key passphrase. If accepted, it will then cache your key using ssh-agent, and forward it to any ssh connection just like keychain. On logout, the agent is stopped, our you can clear your keys with ssh-agent.

It’s just one less step that you have to do on your logins.