A WebmasterWorld thread asks what is that light bulb symbolize on the Yahoo! search results page? You know if comes up for some searches and says "Also try:" keyword phrase here...
Well, besides for it being obviously some sort of search suggestion, I decided to pull up the Yahoo! Search help documentation, which you can find here and you will see it says;
Also Try: When other people have done searches similar to yours, we'll list these queries under the search box. One of these might help you narrow your results. Click on a link to try one of these searches.
Forum discussion at WebmasterWorld.