Remember my previous post on effects one can obtain if zooming in / out while taking a picture? The same effect can easily be obtained just by applying a filter to a perfectly normal image. E.g. this one:

Resulting in the following image (note that any desired degree of blur can be obtained; this one is 10px. The focal point can be anywhere, and affect any size area.):

For comparison, a similar image with the blur obtained by moving the zoom while taking the picture: