The Shake Reduction tool

As the name suggests, Shake Reduction (Enhance>Shake Reduction) is included in the sharpening toolbox and targets those pictures that are not 100% clear. I've always been a bit suspicious of tools like this because, let's face it, if the image is really blurred, there's little we can do to make it really sharp. This tool allows you to select a portion of the image onto which shake reduction, a processor-intensive process, can be imposed.

In the example seen here, I think it actually works well (improved on the right-hand side), but it won't work quite so well on all blurry images. Its efficiency depends on the degree of shake, and the area 
the problem covers in the file. But don't take my word for it—try it yourself and see whether it works on your images.