Your private key should have a strong passphrase. I agree that using a passphrase-less key is bad practice. As for keyloggers, once they obtain your password, t

Your private key should have a strong passphrase. I agree that using a passphrase-less key is bad practice. As for keyloggers, once they obtain your password, they have succeeded. But after obtaining a key's passphrase (which you normally only type in once a local session if using ssh-agent), they still need the key, which may or may not be marginally harder. It's still another step to overcome. So, even if it can be shown to be only a narrow improvement over passwords under certain circumstances, it's a big win in convenience and even security under normal circumstances if done properly. Give it a try, finetune your ~/.ssh/config and you might end up loving it.