Technology Review: New Tricks for Online Photo Editing
This is more than a trick. It appears to me to be a significantly better way to think about reshaping a photograph because it doesn't loose any of the original "message of the photograph". In the illustration to the left, notice that the aspect ratio of the photograph has been changed from landscape to portrait -- without loosing any of the balloons of the landscape version. For me, that is the amazing part of this method.
Check out the video below to hear an explanation about how this is done and then go to the website, rsizr.com to try for yourself.