Join Date: Dec 2008
Location: Perth, Australia
Device: Sony PRS-650, Sony PRS-T3, Kindle 3, iPad2, Nexus7v2
I am afraid not even my engineering degree helps me understand that data set!
Free ebooks are great. Ask Baen, they entice(for good reason) people into buying ongoing series by offering a pretty good selection of free ebooks online. Couple that with extremely competitive pricing (US$6 per book) and it is a winner all round Their sales model works for me and I would be sure others as well!