Many of my clients tell me this is very helpful because it takes the pressure off them and makes the Q&A portion more interesting for the rest of the audience. Here's how it works: Before your presentation ask a few intelligent, informed people if they would serve on your panel. Before starting the Q&A session, tell your audience that to make the session more valuable for them, you have asked some experts to provide answers and input. Then just call on the panel members as the need arises.