Brandon Paddock, who works on the Windows Shell Team here at Microsoft, wrote a Windows Sidebar Gadget that displays the status of the Windows Search Indexer.
Download the Indexer Status Gadget here.
I don’t know about you but I think it’s kind of neat being able to see how many files Windows Search has indexed on my PC right from my desktop. For folks giving the Windows Search 4.0 Preview a try, you can enable “Index Now” functionality (which is reflected in the above screenshot).
Brandon Paddock developed this gadget on his own time and isn’t officially supported by Microsoft. Brandon also developed the Start++ search add-on for Windows Vista.