When running a Google web search from the Google home page or the Google Personalized home page, you can quickly rerun your search (no need to reenter your query terms) in another Google database by simply clicking one or more of the tabs labeled (Images, Groups, News, Froogle, Local, and Desktop (if available and installed). Easy to use, a possible time saver, and easy to explain to novice searchers. Nice!
However, as you know, Google offers many other databases that can be discovered by clicking another link that's visible on the Google home page labeled "more." Here you'll find access to Google Blog Search, Google Directory, Google Scholar, Google Print, and more. The problem, albeit a minor one, is that when you click "more" and then want to run your current query in one of these databases, you need to reenter the entire search string. Believe me, this is not a major issue. However, for allowing a user the chance to carry-over their query (let's say from a web search) to one or more of these databases would be useful.
Perhaps Google should consider providing what Yahoo currently offers on their clutter-free search.yahoo.com page. Here, the user (you don't need to login with a Yahoo ID) can customize which database tabs are visible on their home page. The other useful part (in addition to the customization) is that your search queries will carry over from one database to the next. Let's hope that if/when Yahoo releases their RSS/blog search tool, a tab will become available on the clutter-free page. Bow, note to Yahoo, how about adding Yahoo Audio Search tab option to the clutter-free interface?
I realize that many tools exist like FaganFinder and MrSapo, and Soople (to name only three) that allow you to move from one database to the next with great ease. However, I wanted this post to focus on what Google and Yahoo offer on their native interfaces.