dtucker: Thanks for the response. I'm not suprised I didn't find that, though. Since it is that easy, it really seems appropriate for that to be added to the warning message. I'll suggest that.

If anyone knows a good reason for the warning not to look like this, let me know:

The authenticity of host '192.168.0.123' can't be established.
RSA key fingerprint in md5 is: 59:94:5a:d7:2b:1f:ad:6e:ef:24:4c:71:1d:3c:3b:4a
If you have access to '192.168.0.123' you can run
ssh-keygen -l -f /etc/ssh/ssh_host_rsa_key.pub
on it to verify this key fingerprint.
Are you sure you want to continue connecting(yes/no)?yes
Warning: Permanently added '192.168.0.123' (RSA) to the list of known hosts.