I teach adult education classes in a room full of Macs running OS X. The day classes have an automatic logon in place and I often have to go through a startup, auto login, and then logout before I can get to logging in for my class. I’m thrilled then to read this tip from Chris Breen. He has more tips too on using the Shift key at startup.
When you boot your Mac, wait until the gray screen with the Apple logo disappears and then, when you see the progress window (the white box surrounded by blue), press and hold the Shift key. This skirts auto login and takes you to the list of your Mac’s users.