Searchyc will arrange the results of a search in chronological order, which I find very useful since the date I saw the post is one of the most reliable pieces of information I will typically have on the post.
It is funny that this feature has yet to hit google. I am wanting more and more the ability to sort my google results in chronological order. I recently got a iMac and would love to see the most resent article on how to do things and not ones from 2008!
It's a shame Blekko doesn't seem to crawl news.ycombinator.com much, you could get that information with site:news.ycombinator.com /date [ query ] if they did