UPDATE 4/26/12: Amazon now offers a way to reset the furthest page location from within your account. For details on this new method, check out our post. According to some commenters, below, the new method only works on Amazon-purchased books. So, for imported books, the method below could still be helpful.
One of the great features of Amazon’s Kindle eReader is Whispersync, which will sync your reading progress across multiple devices. For example, you can stop reading in the Kindle for iPad app, and pick up where you left off in the Kindle app on your Android device. A problem arises, though, when you want to reread a book that either you or someone else has already read. Whispersync will remember the end of the book as the “furthest read location,” defeating your ability to pick up where you left off. It takes a one-time workaround, but you can reset the Kindle’s “furthest read location.”