Google has added a timeline view for its real-time results segment. It's minute by minute - and can be interesting to see a story develope.
To see this run a query on something current - eg iceland volcano eruption - click on Show Options - and then on Updates. That story had intense activity on April for most of the day until 6 pm (PDT for west coast).
Google Adds Twitter Timelines, Friend Recommendations, Research Buzz (Apr 15)