No more passwords !

Create a public/private key set with the command:
ssh-keygen -t rsa

then add the public key under ~/.ssh/id_rsa.pub to the remote file user@remotemachine:~/.ssh/authorized_keys
with the perfect script you'll find at the bottom of the page (source http://www.chiark.greenend.org.uk/ucgi/~cjwatson/cvsweb/openssh/contrib/ssh-copy-id)
ssh-copy-id -i ~/.ssh/id_rsa.pub user@remotemachine

The keychain app (mac leopard only) will record the passphrase then you won't need to type anything anymore to login

PS:
    81  15:08   ssh-agent
    82  15:08   ssh-add
    83  15:08   setenv SSH_AUTH_SOCK /tmp/ssh-ZlPOL10214/agent.10214;
    84  15:08   setenv SSH_AGENT_PID 10215;
    85  15:08   echo Agent pid 10215;
    86  15:08   ssh-add