Becoming Your Spouse's Better Half: Why Differences Make a Marriage Great by Rick Johnson for free.  Here is a screenshot, along with Kindle devices for reference.  The paperback edition usually goes for about $10. 7" Multi-Touch Kindle Fire for $199.00 9.7" Wi-Fi 3G Kindle DX for $379.00 6" Wi-Fi Kindle for $109.00 6" Wi-Fi 3G Kindle for $189.00