Unshake is a free program available for all operating systems that takes your blurry photographs and attempts to make them clearer. While it’s not miraculous or perfect, it does in fact help in making photographs more usable, especially at lower resolutions (i.e. for the web).
Here’s a before-and-after example using a quick snapshot I took this past weekend with an outdated point-and-shoot camera:
If you have problems using the program on a Mac, try opening the Unshake.jar file directly at the last step. Larger photographs might also take much longer to “unshake”, while lower-res (i.e. 500px wide) photos were completed very quickly.