Remember as a kid you played with a mirror, putting your face to the side of it and your friends were laughing at the funny symmetry of your face and your faces reflection?
In Photoshop CS6, the new version of Photoshop, you can use special cropping tool and you are done, but that doesn't mean you cannot achieve the same result with older versions.
If you don't want others to use your photos and images without your permission, you can create a so called custom watermark with your name or any other text you want.
