How can I disable ubuntuone-client from running everytime I login?

I need to manually do 'ps and kill -9' to kill it.

Alternatively if you prefer not having everything listed under Startup Application, disable Ubuntu One at login:

echo "Hidden=true" | sudo tee -a /etc/xdg/autostart/ubuntuone-launch.desktop

Show Ubuntu One in Startup Applications:

sudo sed -i "s/NoDisplay=true/NoDisplay=false/g" /etc/xdg/autostart/ubuntuone-launch.desktop

You can use the second command I posted to replace MorganSBailey's command and not effect all startup entries

Open a terminal and type:

sudo sed -i "s/NoDisplay=true/NoDisplay=false/g" /etc/xdg/autostart/*.desktop` 

That will unhide the applications hidden by default in Startup Applications. Now go to Startup Applications, find the Ubuntu One entry and untick it. That should do it.

If you open the Ubuntu One control panel application from the launcher or dash, and go to the Settings tab, you can disable the Connect automatically when computer starts option. This will keep it from connecting automatically on start.

If you do need to actually not run it for some reason, you should do the following:

#: mkdir -p ~/.config/autostart
#: cp /etc/xdg/autostart/ubuntuone-lauch.desktop ~/.config/autostart/
#: echo "X-GNOME-Autostart-enabled=false" >> ~/.config/autostart/ubuntuone-launch.desktop

This will disable the launcher program from running on start. However, it will not disable other applications requesting that ubuntuone-syncdaemon be launched, via DBus, so that they can communicate with it. If any applications do request connection to it, then DBus will automatically launch it.