This quote leapt out at me: "[PowerPoint] wants to organize the talk, to manage the presentation. There's always going to be a slide up, whether you need it th

This quote leapt out at me: "[PowerPoint] wants to organize the talk, to manage the presentation. There's always going to be a slide up, whether you need it there or not. Want to skip over some material? OK, but only by letting the audience watch as you fast-forward awkwardly through the pre-set order. Change the order around to answer a question? Tough..." PowerPoint (and any other presentation software worth its salt) can do this! Press B to replace your current slide with a black screen, W to replace it with a white screen. If you know the slide numbers you can just type a number to jump to that slide and I believe (don't quote me on this, I don't have PowerPoint) you can set keyboard shortcuts to specific slides in advance too. You can set up your display to show a navigator while the projector is showing the current slide, meaning you can pick the next slide manually without exposing the audience to your fumbling. And a little research will reveal many more useful little options. You are in control of your presentation, not the other way around. And the best bit: most people don't even know that these things are possible. So when you do them, it makes you look competent and well-prepared, which makes it more likely that they'll listen to the rest of what you say.