Do you remember the soft-spoken, cigar smoking detective on the hit TV series "Columbo?" Most people do because the show is still in reruns all over the world and once in a while a new episode comes out. One of Detective Columbo's trademarks is that he would start to leave and when he was almost out the door he would stop and say, "Oh. Just one more thing." The same technique can be used by speakers (without the cigar).
Here's how the Columbo technique works: Save one of your really critical points . . . maybe your most important point . . . then completely leave your subject . . . then use the "Oh. Just one more thing" technique and deliver your big point.
Until you've tried this out several times, don't try to use this technique at the end of your speech because people will start shuffling their materials in anticipation of the talk being over.This would cause too much distraction for the technique to have it's full effect.
Begin by using the technique just before a major transition in your talk. That way you will eliminate the shuffling of papers problem noted above. When you get comfortable with this, try the technique before a break. Play with your wording so that you control the audience. Don't say "Well before we take a break . . ." This will start them shuffling. Say something like, "That's all on that topic . . . Oh. and one more thing" . . . then give your main point. As you get really good at controlling the crowd you can try this as your closing. Coming back with the main point will be powerful and memorable.
Oh. Just one more thing . . . .only use this technique ONCE perpresentation. :)