login

For some odd reason, a 2 second delay is included by default when accidentally entering an incorrect username and password combination. This is meant to be a security feature to prevent evil people from brute force attacking your password!

When starting up an Ubuntu computer, for some odd reason it decides to give away all the user logins that are available on that machine. This isn't particularly secure. Yes, these details can be obtained by directly reading the hard drive, but this is significant effort compared to simply turning it on.

To disable the user list, there doesn't seem to be a user interface switch as of Ubuntu 10.04, but there is a command line way to do it.