In the Huffington Post, Denise Brodey has a piece on book trailers. She praises one of the Priceless videos, which is also is rated #1 by reader votes (for the moment, anyway).
Macmillan did something right when they made the video trailer for ebay guru William Poundstone's Priceless. He has this professorial smart cookie approach that makes him watchable and leaves you wanting more.
Just for the record, I've never thought of myself an "eBay guru." While I'd like to believe Brodey's kind words, I'm pretty sure that the high rating of the video on the Huffington site comes down to three simple words: Star Wars underwear.