Virtual Folders

[Grant Thomas]

Is there anything around like the virtual folders in the MS Vista beta, or like Spotlight in OS X?
Incase anyone is not familar with the term virtual folder:
A virtual folder is basically a realtime folder view of saved searches.
The folder looks through the entire index, and logically groups files together by filters instead of putting them in the same physical directory.
I assume it works off of an indexing service.

Any help would be great, I have looked through some of the Debian apt mirrors, and searched google, but have found nothing.