Yahoo! launched a new tool called Yahoo! Search Builder. Tim Mayer of Yahoo! announced it during the Social Search Overview session. With the new Yahoo! Search Builder, you can create a custom Web search engine. The process enables selecting  a set of trusted sites to search the web or you can put the search algorithm to the topic of your choice. Besides, Search Builder also include Site search and News search. The look and feel of the search box and SERPs are also under your control.
With user and traffic reports, you’ll be able to monitor the growth of your search engine.  If you want to know more about it, you can visit Yahoo! Search Blog.