You’re not limited to the widgets provided by Apple on the Mac Dashboard, or the widgets you find available as freeware or for a fee. You can select a portion of a Web page and create a widget that shows the latest version of just that piece, a feature Apple calls WebClips. To create your own widget on the Mac Dashboard, open Safari and go to the Web site you want to turn into a widget. Choose File→Open in Dashboard or click the Dashboard icon. Select the section of the page that you want to capture.
Apple even provides a program, called Dashcode, to help you build your own widget. You can even create a widget to track your favorite blog. The possibilities are endless. Dashcode is in the Xcode folder on your OS X install DVD.
You can even use Apple’s Widget widget to manage all your widgets.