How can I enable SSH without using the gui or apple script on snow leopard?

You can enable SSH from the Terminal with:

sudo launchctl load -w /System/Library/LaunchDaemons/ssh.plist

(note that you need to run this as an admin, and it'll ask for your admin password, which won't echo as you type.)

Here's the command to start VNC sharing -- not SSH, but perhaps it will help you (be sure to replace the password with your own!):

sudo /System/Library/CoreServices/RemoteManagement/ARDAgent.app/Contents/Resources/kickstart -activate -configure -access -on -clientopts -setvnclegacy -vnclegacy yes -clientopts -setvncpw -vncpw PutYourOwnPasswordHere -restart -agent -privs -all

Then you should be able to log in using a VNC client with the password you specified.

Here's the command to stop sharing:

sudo /System/Library/CoreServices/RemoteManagement/ARDAgent.app/Contents/Resources/kickstart -deactivate -configure -access -off

Note that the Sharing pane will NOT show that sharing is active when you turn it on this way via the command line!

Source: http://technotes.twosmallcoins.com/?p=279

sudo systemsetup -setremotelogin on
sudo systemsetup -setremotelogin off