How to embed video and audio into a pdf (ebook):
Adding audio and video to a PDF is actually quite easy.
I think the reason it has not been done much yet is that it does increase the size of the PDF file and hence download time. This is why many PDFs link back to a URL on your web browser.
But with ever increasingly faster + bigger internet connections, there's less reason why not to play the audio or video then and there.
{Please note, you need Adobe Acrobat 6 or higher}
See http://www.totalwebvideo.com/pdfmedia for video tutorial...