For the first time on a Vista machine I found that I had a need for multiple user accounts, even though one of those accounts is only for secure logins to shared drives and remote desktop from one machine to the other. As a result, I never need to directly log in locally and never need to see that username on my login screen. I'd much rather just type in my password and go.
Googling, I found that the same registry key that allowed for this change also works in Vista, the key just doesn't exist. If you don't feel like messing about in the registry, here's the registry key (open notepad, paste in the text below, and then save it as a *.reg file instead of *.txt)
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\SpecialAccounts\UserList]
"username"=dword:00000000
