Most photographers think of blur as an annoyance--something to avoid at all costs. But you can come up with some great uses for blur in photography. Done right, blur can introduce the illusion of motion, for example. Blur can also make your photos "pop" by isolating the subject from the background. You can apply some cool special effects, too, such as zoom blur. In the past I've shown you how to make photos sharper; here I've rounded up a slew of easy-to-apply techniques that can make your photos distinctive through the selective use of blur.