I love Peter Jeff's "Tease 'em to please 'em" analogy. He uses Saturday Night Live's approach to dive right in before you actually introduce yourself. Jeff's acronym is TEASE - which stands for:
The whole idea is to provide information that the audience is fawning over not yawning over!! Cite a celebrity or influential person, tell a story, provide evidence, give examples, and make a statement to verify your information.
Jon Marshall has 5 different ways to "start your presentation off strong."
1) Personal story - people love a good story
2) Joke - risky but excellent if you succeed in being funny
3) Video - could work if it's short and interesting - but you need to tell the audience what and why
4) Thank the audience - show appreciation
5) Ask a question or start a conversation - can work for or against you - if you ask a tired question
Here's a link to Steve Jobs introduction at his 2005 commencement speech to the Yale graduating class - it's short and grabs their attention. http://m.bizcommunity.com/Article/196/98/65331.html.
You will want to listen to the entire 17 minutes because after all it's Steve Jobs. His presentation is incredibly interesting and inspiring.
Your introduction needs to be short, to the point, grab attention. Consequently, prepare your introduction, know it by heart and practice it. Don't sweat over it, just prepare it.