I've linked to a few videos created by authors to promote their books, and I like this one by Janice Taylor for her diet book, "All is Forgiven, Move On." As you'll see, it doesn't try to disguise its amateur origins and has fun along the way. The one thing I'd suggest if you want to do anything like this is to use a shotgun or lapel microphone to get rid of the echoey sound (I've learned his the hard way, as you can tell from some of the earlier videos on my sites).
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