Leopard comes with a nice collection of Dashboard Widgets. However, you can add more widgets to meet your needs.

A few of my favorite widgets:

• iStat Pro allows you to monitor everything about your Mac.
• EasyEnvelopes is just what it implies, an easy way to print envelopes.

There are plenty of great widgets around for you to download. The Apple downloads page is the best source.

You can also create your own Widgets. There are two methods:

• You can cut a snippet from a web page and turn that into a Widget using the "Open in Dashboard" button on the Safari toolbar. This creates a very simple Widget view of the web content. Don't have that button on your Safari toolbar? You can add it by following the menus View > Cutsomize Toolbar.
• A more complex Widget is nothing more than a JavaScript based client that uses an Apple supplied script library for special functions. Apple's Dashboard Programming page is the best source for details.