I love the way the RSS Visualizer screen saver looks, especially on my TV. The only thing I don't like about it is the blue background. So I opened it up in Quartz Composer (it's damn cool they offered it up that way), and I changed the background to black. It looks much cleaner now. Here's a link to the file. Enjoy!
[robg adds: If you haven't had the chance to play with Quartz Composer yet, it's worth the time. It's an amazingly useful little program. I was playing around with a macosxhints' RSS screensaver in it, and I was impressed at how (relatively) simple it was to figure out the basics. You'll have to install XCode to get it, but (in my opinion) it's worth the effort.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20050425173919124