I think if you counted the people who (by default) use Google or Yahoo search, you'd probably account for 85% of internet users - maybe more. But is limiting yourself to only one search the best technique for finding stuff? A while back I blogged about a search that uses 36 of the most popular search resources on one page, but you can only use one at a time.
Addictomatic lets you search and displays the results in little sections including various news sites, YouTube, Digg, Google blog search, Wordpress blogs and technorati - all customizable to your tastes. The pic to the right doesn't even represent half of the page of search results you'll get.