I just got SSHKeychain working on my powerbook. Then I was able to customize the X11 menus so I can bring up applications on all the machines I work on without having to type any damn passwords. As the name implies, it also works with the Apple keychain, so if I have that unlocked, it doesn't even ask me for my ssh key passphrase. That last makes me a little nervous... I think the latter is more secure than the former (but I'm not sure), so I may turn that feature off.