I came up with a few more to add to Rod Paddock's fantastic list of speaker anti-patterns.
13. Turn OFF your Instant Messenger client. It is distracting for the audience to see you're receiving a message. BTW, if you're using MSN Live Messenger make sure you shut down Windows Messenger as well since it can take over if it sees MSN Live Messenger is off.
14. Close all programs not necessary for the presentation, especially Microsoft Outlook. It is distracting for the audience to see you've got new mail. The ONLY software running while you're presenting is the software you're using for the presentation. Which leads me to this next one....
15. Open all the programs (and files!) you're going to need for your presentation BEFORE you begin. The audience does not need to watch you launching Visual Studio, SQL Server Management Studio, Internet Explorer, or whatever software will be utilized in the presentation. As part of my preparation, I keep a list of all the programs required for the presentation.
Have a day. :-|