Back in June I wrote about Widgets Preference Pane, which is a Mac OS X preference pane (as I'm sure you guessed) that gives you great control over Dashboard and your widets. Use it to quickly view all of your installed widgets, deactivate, activate or delete any of them, install new widgets via drag and drop and much more. You can also replace the widget bar's default perforated metal background. Use one of the supplied alternate backgrounds or make your own.
If you're like me - not the artistic type - visit Pixeldecor. Owner Jen has made several graphics specifically for replacing the metal backdrop, each with a cool, retro feel. Check it out.