Knovio is a new service for delivering presentations online. To use Knovio you upload your slides to the site then use your webcam to record a video of yourself talking about the slides. When you're finished your video and slides will be synchronized and displayed side-by-side. Knovio presentations can be embedded into your blog or website. Knovio is currently in a private beta stage so you do have to register and wait for an invitation to the service.
Applications for Education
Knovio appears to be similar to Slide Six and Slideshare's Zipcast service. All three of these services could be used by teachers who are using the "flipped" classroom model.