I recently gave a presentation at ToorCon 8 in San Diego on the subject of VoIP attacks. You can find slides and video here. A writeup from Wired News can also be found here.
My presentation earlier today went very well. Other than a few technical difficulties with the A/V setup regarding my laptop audio and running out of time with about 4 slides and my conclusion left and having to rush through the end, I was very happy with it. Slides in various formats and video of my talk can be found here.