A very cool article on www.paidcontent.org today on how much authors in the Amazon Kindle Singles program are making. The Kindle Singles program is their 30,000ish word, shorter book program. The Kindle is just flying and we should all be pushing our material out through this channel. You kind of have to be invited or be somewhat established to be in the Single program but you don't have to be anything to put your book up Amazon and Kindle itself.
Here is the article on some of the top ten bestselling authors on the Kindle Single