There's yet another search engine looking to capture a market foothold. Prefound.com has just come out of beta with a service using tagging and community participation to differentiate itself. When you do a search with Prefound, rather than seeing a list of Web sites, you are - theoretically - presented with a group of sites that have been organized and uploaded by a Prefound member. Prefound CEO Steve Mansfield said this approach lets users easily access search results that offer links to Web sites, video and podcasts. Mansfield believes there's fertile ground for human-based search Web indexing as a complement to the powerful algorithms being used by Google, Yahoo, Microsoft, etc.  In some sense, the Prefound approach harkens back to what Jerry Yang and David Filo did when they first launched Yahoo! To help build the database, Prefound is leaning heavily on work done by the Open Directory Project. Design Technica has a mini-review on Prefound. Like most Web 2.0 start-ups, Prefound is relying on paid-search links from ePilot to generate revenue.