LightDM is the login screen you see once your Ubuntu machine starts up. It’s a lot better than the old days when you were dropped at a terminal prompt. The following will show you how to customize LightDM with themes and backgrounds to dress up that dull look.
If you have heard of Linux Mint, you will be pleased to know that the latest release (Linux Mint 14) comes with a new login manager – MDM Display Manager, that is both beautiful and customizable. Here is how you can get it on your Ubuntu.