Can you suggest a topic for research in the field of Search Technologies?

Blog search. Traditional search engines simply crawl the network to find pages to add to their listing, but this approach does not work in a blogging environment, where you may have 100,000 pages updated in less than a day. The question is, how do you arrange your search network to accept pings from pages when they are updated as well as simply crawling? This is the problem that Technorati and Icerocket, among others, are working on.