Attached Link: http://www.ethervizion.com/gallery/images/simple_surreal/simple2.jpg

See attached link for an example of motion blurring. bloodsong pretty much tells you what you need to do. Setup an animation so that whatever you want blurred is in motion. Best results are obtained if you setup your beginning and end keyframe so that the object is where you want it around the halfway time point between the two keyframes. Rendering on the first or last keyframe sometimes has problems if your objects accelerates and slows to have zero velocity at those points. So, move the time slider so that your object is in the correct position, then render in either 'Broadcast' or 'Ultra' mode. This is key - 'Final' mode does not render motion blur. Hope this helps. -Karl