Cuil is Wikipedia.founded by two former Google employees. It "organizes web pages by content and displays relatively long entries along with thumbnail pictures for many results," according to
You can see an example of the time line function by looking at these Cuil search results for the Great Depression. Notice the time line window on the right of the screen. It stays there, even as you progress to more pages of the search. That particular search time line has entries covering a period ranging from 1929 to 1939. Mousing over the entries gets you more details.
I suspect the time line feature will add to Cuil's popularity.