I have a Win 2003 server that hosts hundreds of web sites. I'm constantly using the rotten Windows search tool to find files via RDP. My typical search would be to find any mention of things in the code of the sites, for instance a variable name, or a hard-coded email address.
Google desktop might be the ticket if it was a workstation, but the desktop search only runs when the user is logged in (which is pretty much never).
I'd love to find a better file finder! Maybe something like Mac OS/X spotlight.
The key is that it has to index as a service, so a user doesn't have to be logged in.