Annoyed and bored with the same standard login screen? Here's how to turn it into one of your own images.
1. Open the Terminal
2. Type
sudo -i and enter your password.
3. Type
xhost +SI:localuser:lightdm
4. Type
sudo su lightdm -s /bin/bash
5. Type
gsettings set com.canonical.unity-greeter draw-user-backgrounds 'false'
6. Type (replacing imagelocation.jpg with the location of your chosen image)
gsettings set com.canonical.unity-greeter background '/imagelocation.jpg'
7. Type gsettings set com.canonical.unity-greeter draw-grid 'false' to remove the dotted lines uBuntu that appear.
Restart uBuntu and you should be good to go!