MyHeritage.com is a genealogy web site that's been around for a while, but just recently enhanced their "supersearch." The database is large, multilingual, diverse, speedy, easy-- and free. Past complaints about having to download lots of software seem to have been heeded with the new release. On the down side, though, is the number of hits which are not free or not public.
The A goes to Cheapflightfinder.com. Finding the best airfare for a particular flight is, shall we say, an inexact science. The apples differ from the oranges, the costs are different for every flight and change by the minute, blah, blah, blah. We've all had the same frustrations. The meta search engines (Kayak, Trip Adviser, Mobissimo, Expedia, etc) each seem to bring order to the chaos. The problem is that each of these order-bringers comes up with very different results. Enter Cheapflightfinder.com--a meta meta search engine--which compares the best fares of 16 flight comparison sites. It's not perfect: Unless I'm missing something, you still have to navigate through multiple windows to actually compare the various sites. It's definitely one to try, though.