Dan Barker posted a screen shot on Twitter of an interesting new search feature within the Google search results named "People also ask." Here is a picture:
As you can see, this is one of those search expansion tools, similar to the related searches section you'd see at the bottom of the search results.
But the "People may also ask" feature seems way more in your face, encouraging you to click on the results, which would generate another search.
Here is another picture from Dan:
Forum discussion at Twitter.
Update: Here is a picture from @kieranheadley on what it looks like to expand: