Tafiti, which means "do research" in Swahili language, is a different search tool that we are not familiar with so much when you think about the alternatives. It uses Silverlight technology for visualization and Live Search as the underlying search technology. With a combination of these two important Technologies; tafiti gives a different user experience. If you haven’t used Tafiti, I recommend you to watch screencast that I recorded and try it yourself: www.tafiti.com
If you like the idea of getting Silverlight and Live Search together, I also recommend you to look Windows Live Quick Applications (beta) site and also you can download Tafiti code that is available now.